/* libFLAC - Free Lossless Audio Codec library
 * Copyright (C) 2000,2001,2002,2003,2004,2005,2006,2007  Josh Coalson
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *
 * - Redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution.
 *
 * - Neither the name of the Xiph.org Foundation nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#if HAVE_CONFIG_H
    #include <config.h>
#endif

#if defined _MSC_VER || defined __MINGW32__
    #include <io.h> /* for _setmode() */
    #include <fcntl.h> /* for _O_BINARY */
#endif
#if defined __CYGWIN__ || defined __EMX__
    #include <io.h> /* for setmode(), O_BINARY */
    #include <fcntl.h> /* for _O_BINARY */
#endif
#include <stdio.h>
#include <stdlib.h> /* for malloc() */
#include <string.h> /* for memset/memcpy() */
#include <sys/stat.h> /* for stat() */
#include <sys/types.h> /* for off_t */
#if defined _MSC_VER || defined __BORLANDC__ || defined __MINGW32__
    #if _MSC_VER <= 1600 || defined __BORLANDC__ /* @@@ [2G limit] */
        #define fseeko fseek
        #define ftello ftell
    #endif
#endif
#include "public/assert_flac.h"
#include "share/alloc.h"
#include "protected/stream_decoder.h"
#include "private/bitreader.h"
#include "private/bitmath.h"
#include "private/cpu.h"
#include "private/crc.h"
#include "private/fixed.h"
#include "private/format.h"
#include "private/lpc.h"
#include "private/md5.h"
#include "private/memory.h"

#ifdef max
    #undef max
#endif
#define max(a, b) ((a) > (b) ? (a) : (b))

/* adjust for compilers that can't understand using LLU suffix for uint64_t literals */
#ifdef _MSC_VER
    #define FLAC__U64L(x) x
#else
    #define FLAC__U64L(x) x##LLU
#endif


/* technically this should be in an "export.c" but this is convenient enough */
FLAC_API int FLAC_API_SUPPORTS_OGG_FLAC =
#if FLAC__HAS_OGG
    1
#else
    0
#endif
;


/***********************************************************************
*
* Private static data
*
***********************************************************************/

static FLAC__byte ID3V2_TAG_[3] = { 'I', 'D', '3' };

/***********************************************************************
*
* Private class method prototypes
*
***********************************************************************/

static void set_defaults_(FLAC__StreamDecoder* decoder);
static FILE * get_binary_stdin_();
static FLAC__bool allocate_output_(FLAC__StreamDecoder* decoder, unsigned size, unsigned channels);
static FLAC__bool has_id_filtered_(FLAC__StreamDecoder* decoder, FLAC__byte* id);
static FLAC__bool find_metadata_(FLAC__StreamDecoder* decoder);
static FLAC__bool read_metadata_(FLAC__StreamDecoder* decoder);
static FLAC__bool read_metadata_streaminfo_(FLAC__StreamDecoder* decoder, FLAC__bool is_last, unsigned length);
static FLAC__bool read_metadata_seektable_(FLAC__StreamDecoder* decoder, FLAC__bool is_last, unsigned length);
static FLAC__bool read_metadata_vorbiscomment_(FLAC__StreamDecoder* decoder, FLAC__StreamMetadata_VorbisComment* obj);
static FLAC__bool read_metadata_cuesheet_(FLAC__StreamDecoder* decoder, FLAC__StreamMetadata_CueSheet* obj);
static FLAC__bool read_metadata_picture_(FLAC__StreamDecoder* decoder, FLAC__StreamMetadata_Picture* obj);
static FLAC__bool skip_id3v2_tag_(FLAC__StreamDecoder* decoder);
static FLAC__bool frame_sync_(FLAC__StreamDecoder* decoder);
static FLAC__bool read_frame_(FLAC__StreamDecoder* decoder, FLAC__bool* got_a_frame, FLAC__bool do_full_decode);
static FLAC__bool read_frame_header_(FLAC__StreamDecoder* decoder);
static FLAC__bool read_subframe_(FLAC__StreamDecoder* decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode);
static FLAC__bool read_subframe_constant_(FLAC__StreamDecoder* decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode);
static FLAC__bool read_subframe_fixed_(FLAC__StreamDecoder* decoder, unsigned channel, unsigned bps, const unsigned order, FLAC__bool do_full_decode);
static FLAC__bool read_subframe_lpc_(FLAC__StreamDecoder* decoder, unsigned channel, unsigned bps, const unsigned order, FLAC__bool do_full_decode);
static FLAC__bool read_subframe_verbatim_(FLAC__StreamDecoder* decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode);
static FLAC__bool read_residual_partitioned_rice_(FLAC__StreamDecoder* decoder, unsigned predictor_order, unsigned partition_order, FLAC__EntropyCodingMethod_PartitionedRiceContents* partitioned_rice_contents, FLAC__int32* residual, FLAC__bool is_extended);
static FLAC__bool read_zero_padding_(FLAC__StreamDecoder* decoder);
static FLAC__bool read_callback_(FLAC__byte buffer[], size_t* bytes, void* client_data);
#if FLAC__HAS_OGG
static FLAC__StreamDecoderReadStatus read_callback_ogg_aspect_(const FLAC__StreamDecoder* decoder, FLAC__byte buffer[], size_t* bytes);
static FLAC__OggDecoderAspectReadStatus read_callback_proxy_(const void* void_decoder, FLAC__byte buffer[], size_t* bytes, void* client_data);
#endif
static FLAC__StreamDecoderWriteStatus write_audio_frame_to_client_(FLAC__StreamDecoder* decoder, const FLAC__Frame* frame, const FLAC__int32* const buffer[]);
static void send_error_to_client_(const FLAC__StreamDecoder* decoder, FLAC__StreamDecoderErrorStatus status);
static FLAC__bool seek_to_absolute_sample_(FLAC__StreamDecoder* decoder, FLAC__uint64 stream_length, FLAC__uint64 target_sample);
#if FLAC__HAS_OGG
static FLAC__bool seek_to_absolute_sample_ogg_(FLAC__StreamDecoder* decoder, FLAC__uint64 stream_length, FLAC__uint64 target_sample);
#endif
static FLAC__StreamDecoderReadStatus file_read_callback_(const FLAC__StreamDecoder* decoder, FLAC__byte buffer[], size_t* bytes, void* client_data);
static FLAC__StreamDecoderSeekStatus file_seek_callback_(const FLAC__StreamDecoder* decoder, FLAC__uint64 absolute_byte_offset, void* client_data);
static FLAC__StreamDecoderTellStatus file_tell_callback_(const FLAC__StreamDecoder* decoder, FLAC__uint64* absolute_byte_offset, void* client_data);
static FLAC__StreamDecoderLengthStatus file_length_callback_(const FLAC__StreamDecoder* decoder, FLAC__uint64* stream_length, void* client_data);
static FLAC__bool file_eof_callback_(const FLAC__StreamDecoder* decoder, void* client_data);

/***********************************************************************
*
* Private class data
*
***********************************************************************/

typedef struct FLAC__StreamDecoderPrivate
{
    #if FLAC__HAS_OGG
    FLAC__bool is_ogg;
    #endif
    FLAC__StreamDecoderReadCallback read_callback;
    FLAC__StreamDecoderSeekCallback seek_callback;
    FLAC__StreamDecoderTellCallback tell_callback;
    FLAC__StreamDecoderLengthCallback length_callback;
    FLAC__StreamDecoderEofCallback eof_callback;
    FLAC__StreamDecoderWriteCallback write_callback;
    FLAC__StreamDecoderMetadataCallback metadata_callback;
    FLAC__StreamDecoderErrorCallback error_callback;
    /* generic 32-bit datapath: */
    void (* local_lpc_restore_signal)(const FLAC__int32 residual[], unsigned data_len, const FLAC__int32 qlp_coeff[], unsigned order, int lp_quantization, FLAC__int32 data[]);
    /* generic 64-bit datapath: */
    void (* local_lpc_restore_signal_64bit)(const FLAC__int32 residual[], unsigned data_len, const FLAC__int32 qlp_coeff[], unsigned order, int lp_quantization, FLAC__int32 data[]);
    /* for use when the signal is <= 16 bits-per-sample, or <= 15 bits-per-sample on a side channel (which requires 1 extra bit): */
    void (* local_lpc_restore_signal_16bit)(const FLAC__int32 residual[], unsigned data_len, const FLAC__int32 qlp_coeff[], unsigned order, int lp_quantization, FLAC__int32 data[]);
    /* for use when the signal is <= 16 bits-per-sample, or <= 15 bits-per-sample on a side channel (which requires 1 extra bit), AND order <= 8: */
    void (* local_lpc_restore_signal_16bit_order8)(const FLAC__int32 residual[], unsigned data_len, const FLAC__int32 qlp_coeff[], unsigned order, int lp_quantization, FLAC__int32 data[]);
    FLAC__bool (* local_bitreader_read_rice_signed_block)(FLAC__BitReader* br, int vals[], unsigned nvals, unsigned parameter);
    void* client_data;
    FILE* file; /* only used if FLAC__stream_decoder_init_file()/FLAC__stream_decoder_init_file() called, else nullptr */
    FLAC__BitReader* input;
    FLAC__int32* output[FLAC__MAX_CHANNELS];
    FLAC__int32* residual[FLAC__MAX_CHANNELS]; /* WATCHOUT: these are the aligned pointers; the real pointers that should be free()'d are residual_unaligned[] below */
    FLAC__EntropyCodingMethod_PartitionedRiceContents partitioned_rice_contents[FLAC__MAX_CHANNELS];
    unsigned output_capacity, output_channels;
    FLAC__uint32 fixed_block_size, next_fixed_block_size;
    FLAC__uint64 samples_decoded;
    FLAC__bool has_stream_info, has_seek_table;
    FLAC__StreamMetadata stream_info;
    FLAC__StreamMetadata seek_table;
    FLAC__bool metadata_filter[128]; /* MAGIC number 128 == total number of metadata block types == 1 << 7 */
    FLAC__byte* metadata_filter_ids;
    size_t metadata_filter_ids_count, metadata_filter_ids_capacity; /* units for both are IDs, not bytes */
    FLAC__Frame frame;
    FLAC__bool cached; /* true if there is a byte in lookahead */
    FLAC__CPUInfo cpuinfo;
    FLAC__byte header_warmup[2]; /* contains the sync code and reserved bits */
    FLAC__byte lookahead; /* temp storage when we need to look ahead one byte in the stream */
    /* unaligned (original) pointers to allocated data */
    FLAC__int32* residual_unaligned[FLAC__MAX_CHANNELS];
    FLAC__bool do_md5_checking; /* initially gets protected_->md5_checking but is turned off after a seek or if the metadata has a zero MD5 */
    FLAC__bool internal_reset_hack; /* used only during init() so we can call reset to set up the decoder without rewinding the input */
    FLAC__bool is_seeking;
    FLAC__MD5Context md5context;
    FLAC__byte computed_md5sum[16]; /* this is the sum we computed from the decoded data */
    /* (the rest of these are only used for seeking) */
    FLAC__Frame last_frame; /* holds the info of the last frame we seeked to */
    FLAC__uint64 first_frame_offset; /* hint to the seek routine of where in the stream the first audio frame starts */
    FLAC__uint64 target_sample;
    unsigned unparseable_frame_count; /* used to tell whether we're decoding a future version of FLAC or just got a bad sync */
    #if FLAC__HAS_OGG
    FLAC__bool got_a_frame; /* hack needed in Ogg FLAC seek routine to check when process_single() actually writes a frame */
    #endif
} FLAC__StreamDecoderPrivate;

/***********************************************************************
*
* Public static class data
*
***********************************************************************/

FLAC_API const char* const FLAC__StreamDecoderStateString[] = {
    "FLAC__STREAM_DECODER_SEARCH_FOR_METADATA",
    "FLAC__STREAM_DECODER_READ_METADATA",
    "FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC",
    "FLAC__STREAM_DECODER_READ_FRAME",
    "FLAC__STREAM_DECODER_END_OF_STREAM",
    "FLAC__STREAM_DECODER_OGG_ERROR",
    "FLAC__STREAM_DECODER_SEEK_ERROR",
    "FLAC__STREAM_DECODER_ABORTED",
    "FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR",
    "FLAC__STREAM_DECODER_UNINITIALIZED"
};

FLAC_API const char* const FLAC__StreamDecoderInitStatusString[] = {
    "FLAC__STREAM_DECODER_INIT_STATUS_OK",
    "FLAC__STREAM_DECODER_INIT_STATUS_UNSUPPORTED_CONTAINER",
    "FLAC__STREAM_DECODER_INIT_STATUS_INVALID_CALLBACKS",
    "FLAC__STREAM_DECODER_INIT_STATUS_MEMORY_ALLOCATION_ERROR",
    "FLAC__STREAM_DECODER_INIT_STATUS_ERROR_OPENING_FILE",
    "FLAC__STREAM_DECODER_INIT_STATUS_ALREADY_INITIALIZED"
};

FLAC_API const char* const FLAC__StreamDecoderReadStatusString[] = {
    "FLAC__STREAM_DECODER_READ_STATUS_CONTINUE",
    "FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM",
    "FLAC__STREAM_DECODER_READ_STATUS_ABORT"
};

FLAC_API const char* const FLAC__StreamDecoderSeekStatusString[] = {
    "FLAC__STREAM_DECODER_SEEK_STATUS_OK",
    "FLAC__STREAM_DECODER_SEEK_STATUS_ERROR",
    "FLAC__STREAM_DECODER_SEEK_STATUS_UNSUPPORTED"
};

FLAC_API const char* const FLAC__StreamDecoderTellStatusString[] = {
    "FLAC__STREAM_DECODER_TELL_STATUS_OK",
    "FLAC__STREAM_DECODER_TELL_STATUS_ERROR",
    "FLAC__STREAM_DECODER_TELL_STATUS_UNSUPPORTED"
};

FLAC_API const char* const FLAC__StreamDecoderLengthStatusString[] = {
    "FLAC__STREAM_DECODER_LENGTH_STATUS_OK",
    "FLAC__STREAM_DECODER_LENGTH_STATUS_ERROR",
    "FLAC__STREAM_DECODER_LENGTH_STATUS_UNSUPPORTED"
};

FLAC_API const char* const FLAC__StreamDecoderWriteStatusString[] = {
    "FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE",
    "FLAC__STREAM_DECODER_WRITE_STATUS_ABORT"
};

FLAC_API const char* const FLAC__StreamDecoderErrorStatusString[] = {
    "FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC",
    "FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER",
    "FLAC__STREAM_DECODER_ERROR_STATUS_FRAME_CRC_MISMATCH",
    "FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM"
};

/***********************************************************************
*
* Class constructor/destructor
*
***********************************************************************/
FLAC_API FLAC__StreamDecoder * FLAC__stream_decoder_new()
{
    FLAC__StreamDecoder* decoder;
    unsigned i;

    FLAC__ASSERT(sizeof(int) >= 4); /* we want to die right away if this is not true */

    decoder = (FLAC__StreamDecoder*)calloc(1, sizeof(FLAC__StreamDecoder));
    if (decoder == 0)
    {
        return 0;
    }

    decoder->protected_ = (FLAC__StreamDecoderProtected*)calloc(1, sizeof(FLAC__StreamDecoderProtected));
    if (decoder->protected_ == 0)
    {
        free(decoder);
        return 0;
    }

    decoder->private_ = (FLAC__StreamDecoderPrivate*)calloc(1, sizeof(FLAC__StreamDecoderPrivate));
    if (decoder->private_ == 0)
    {
        free(decoder->protected_);
        free(decoder);
        return 0;
    }

    decoder->private_->input = FLAC__bitreader_new();
    if (decoder->private_->input == 0)
    {
        free(decoder->private_);
        free(decoder->protected_);
        free(decoder);
        return 0;
    }

    decoder->private_->metadata_filter_ids_capacity = 16;
    if (0 == (decoder->private_->metadata_filter_ids = (FLAC__byte*)malloc((FLAC__STREAM_METADATA_APPLICATION_ID_LEN / 8) * decoder->private_->metadata_filter_ids_capacity)))
    {
        FLAC__bitreader_delete(decoder->private_->input);
        free(decoder->private_);
        free(decoder->protected_);
        free(decoder);
        return 0;
    }

    for (i = 0; i < FLAC__MAX_CHANNELS; i++)
    {
        decoder->private_->output[i] = 0;
        decoder->private_->residual_unaligned[i] = decoder->private_->residual[i] = 0;
    }

    decoder->private_->output_capacity = 0;
    decoder->private_->output_channels = 0;
    decoder->private_->has_seek_table = false;

    for (i = 0; i < FLAC__MAX_CHANNELS; i++)
        FLAC__format_entropy_coding_method_partitioned_rice_contents_init(&decoder->private_->partitioned_rice_contents[i]);

    decoder->private_->file = 0;

    set_defaults_(decoder);

    decoder->protected_->state = FLAC__STREAM_DECODER_UNINITIALIZED;

    return decoder;
}

FLAC_API void FLAC__stream_decoder_delete(FLAC__StreamDecoder* decoder)
{
    unsigned i;

    FLAC__ASSERT(0 != decoder);
    FLAC__ASSERT(0 != decoder->protected_);
    FLAC__ASSERT(0 != decoder->private_);
    FLAC__ASSERT(0 != decoder->private_->input);

    FLAC__stream_decoder_finish(decoder);

    if (0 != decoder->private_->metadata_filter_ids)
        free(decoder->private_->metadata_filter_ids);

    FLAC__bitreader_delete(decoder->private_->input);

    for (i = 0; i < FLAC__MAX_CHANNELS; i++)
        FLAC__format_entropy_coding_method_partitioned_rice_contents_clear(&decoder->private_->partitioned_rice_contents[i]);

    free(decoder->private_);
    free(decoder->protected_);
    free(decoder);
}

/***********************************************************************
*
* Public class methods
*
***********************************************************************/

static FLAC__StreamDecoderInitStatus init_stream_internal_(
    FLAC__StreamDecoder* decoder,
    FLAC__StreamDecoderReadCallback read_callback,
    FLAC__StreamDecoderSeekCallback seek_callback,
    FLAC__StreamDecoderTellCallback tell_callback,
    FLAC__StreamDecoderLengthCallback length_callback,
    FLAC__StreamDecoderEofCallback eof_callback,
    FLAC__StreamDecoderWriteCallback write_callback,
    FLAC__StreamDecoderMetadataCallback metadata_callback,
    FLAC__StreamDecoderErrorCallback error_callback,
    void* client_data,
    FLAC__bool is_ogg
    )
{
    FLAC__ASSERT(0 != decoder);

    if (decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
        return FLAC__STREAM_DECODER_INIT_STATUS_ALREADY_INITIALIZED;

    #if !FLAC__HAS_OGG
    if (is_ogg)
        return FLAC__STREAM_DECODER_INIT_STATUS_UNSUPPORTED_CONTAINER;
    #endif

    if (
        0 == read_callback ||
        0 == write_callback ||
        0 == error_callback ||
        (seek_callback && (0 == tell_callback || 0 == length_callback || 0 == eof_callback))
        )
        return FLAC__STREAM_DECODER_INIT_STATUS_INVALID_CALLBACKS;

    #if FLAC__HAS_OGG
    decoder->private_->is_ogg = is_ogg;
    if (is_ogg && !FLAC__ogg_decoder_aspect_init(&decoder->protected_->ogg_decoder_aspect))
        return (FLAC__StreamDecoderInitStatus)(decoder->protected_->state = FLAC__STREAM_DECODER_OGG_ERROR);
    #endif

    /*
     * get the CPU info and set the function pointers
     */
    FLAC__cpu_info(&decoder->private_->cpuinfo);
    /* first default to the non-asm routines */
    decoder->private_->local_lpc_restore_signal = FLAC__lpc_restore_signal;
    decoder->private_->local_lpc_restore_signal_64bit = FLAC__lpc_restore_signal_wide;
    decoder->private_->local_lpc_restore_signal_16bit = FLAC__lpc_restore_signal;
    decoder->private_->local_lpc_restore_signal_16bit_order8 = FLAC__lpc_restore_signal;
    decoder->private_->local_bitreader_read_rice_signed_block = FLAC__bitreader_read_rice_signed_block;
    /* now override with asm where appropriate */
    #ifndef FLAC__NO_ASM
    if (decoder->private_->cpuinfo.use_asm)
    {
        #ifdef FLAC__CPU_IA32
        FLAC__ASSERT(decoder->private_->cpuinfo.type == FLAC__CPUINFO_TYPE_IA32);
        #ifdef FLAC__HAS_NASM
        #if 1 /*@@@@@@ OPT: not clearly faster, needs more testing */
        if (decoder->private_->cpuinfo.data.ia32.bswap)
            decoder->private_->local_bitreader_read_rice_signed_block = FLAC__bitreader_read_rice_signed_block_asm_ia32_bswap;
        #endif
        if (decoder->private_->cpuinfo.data.ia32.mmx)
        {
            decoder->private_->local_lpc_restore_signal = FLAC__lpc_restore_signal_asm_ia32;
            decoder->private_->local_lpc_restore_signal_16bit = FLAC__lpc_restore_signal_asm_ia32_mmx;
            decoder->private_->local_lpc_restore_signal_16bit_order8 = FLAC__lpc_restore_signal_asm_ia32_mmx;
        }
        else
        {
            decoder->private_->local_lpc_restore_signal = FLAC__lpc_restore_signal_asm_ia32;
            decoder->private_->local_lpc_restore_signal_16bit = FLAC__lpc_restore_signal_asm_ia32;
            decoder->private_->local_lpc_restore_signal_16bit_order8 = FLAC__lpc_restore_signal_asm_ia32;
        }
        #endif
        #elif defined FLAC__CPU_PPC
        FLAC__ASSERT(decoder->private_->cpuinfo.type == FLAC__CPUINFO_TYPE_PPC);
        if (decoder->private_->cpuinfo.data.ppc.altivec)
        {
            decoder->private_->local_lpc_restore_signal_16bit = FLAC__lpc_restore_signal_asm_ppc_altivec_16;
            decoder->private_->local_lpc_restore_signal_16bit_order8 = FLAC__lpc_restore_signal_asm_ppc_altivec_16_order8;
        }
        #endif
    }
    #endif

    /* from here on, errors are fatal */

    if (!FLAC__bitreader_init(decoder->private_->input, decoder->private_->cpuinfo, read_callback_, decoder))
    {
        decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
        return FLAC__STREAM_DECODER_INIT_STATUS_MEMORY_ALLOCATION_ERROR;
    }

    decoder->private_->read_callback = read_callback;
    decoder->private_->seek_callback = seek_callback;
    decoder->private_->tell_callback = tell_callback;
    decoder->private_->length_callback = length_callback;
    decoder->private_->eof_callback = eof_callback;
    decoder->private_->write_callback = write_callback;
    decoder->private_->metadata_callback = metadata_callback;
    decoder->private_->error_callback = error_callback;
    decoder->private_->client_data = client_data;
    decoder->private_->fixed_block_size = decoder->private_->next_fixed_block_size = 0;
    decoder->private_->samples_decoded = 0;
    decoder->private_->has_stream_info = false;
    decoder->private_->cached = false;

    decoder->private_->do_md5_checking = decoder->protected_->md5_checking;
    decoder->private_->is_seeking = false;

    decoder->private_->internal_reset_hack = true; /* so the following reset does not try to rewind the input */
    if (!FLAC__stream_decoder_reset(decoder))
    {
        /* above call sets the state for us */
        return FLAC__STREAM_DECODER_INIT_STATUS_MEMORY_ALLOCATION_ERROR;
    }

    return FLAC__STREAM_DECODER_INIT_STATUS_OK;
}

FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_stream(
    FLAC__StreamDecoder* decoder,
    FLAC__StreamDecoderReadCallback read_callback,
    FLAC__StreamDecoderSeekCallback seek_callback,
    FLAC__StreamDecoderTellCallback tell_callback,
    FLAC__StreamDecoderLengthCallback length_callback,
    FLAC__StreamDecoderEofCallback eof_callback,
    FLAC__StreamDecoderWriteCallback write_callback,
    FLAC__StreamDecoderMetadataCallback metadata_callback,
    FLAC__StreamDecoderErrorCallback error_callback,
    void* client_data
    )
{
    return init_stream_internal_(
               decoder,
               read_callback,
               seek_callback,
               tell_callback,
               length_callback,
               eof_callback,
               write_callback,
               metadata_callback,
               error_callback,
               client_data,
               /*is_ogg=*/ false
               );
}

FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_ogg_stream(
    FLAC__StreamDecoder* decoder,
    FLAC__StreamDecoderReadCallback read_callback,
    FLAC__StreamDecoderSeekCallback seek_callback,
    FLAC__StreamDecoderTellCallback tell_callback,
    FLAC__StreamDecoderLengthCallback length_callback,
    FLAC__StreamDecoderEofCallback eof_callback,
    FLAC__StreamDecoderWriteCallback write_callback,
    FLAC__StreamDecoderMetadataCallback metadata_callback,
    FLAC__StreamDecoderErrorCallback error_callback,
    void* client_data
    )
{
    return init_stream_internal_(
               decoder,
               read_callback,
               seek_callback,
               tell_callback,
               length_callback,
               eof_callback,
               write_callback,
               metadata_callback,
               error_callback,
               client_data,
               /*is_ogg=*/ true
               );
}

static FLAC__StreamDecoderInitStatus init_FILE_internal_(
    FLAC__StreamDecoder* decoder,
    FILE* file,
    FLAC__StreamDecoderWriteCallback write_callback,
    FLAC__StreamDecoderMetadataCallback metadata_callback,
    FLAC__StreamDecoderErrorCallback error_callback,
    void* client_data,
    FLAC__bool is_ogg
    )
{
    FLAC__ASSERT(0 != decoder);
    FLAC__ASSERT(0 != file);

    if (decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
        return (FLAC__StreamDecoderInitStatus)(decoder->protected_->state = (FLAC__StreamDecoderState)FLAC__STREAM_DECODER_INIT_STATUS_ALREADY_INITIALIZED);

    if (0 == write_callback || 0 == error_callback)
        return (FLAC__StreamDecoderInitStatus)(decoder->protected_->state = (FLAC__StreamDecoderState)FLAC__STREAM_DECODER_INIT_STATUS_INVALID_CALLBACKS);

    /*
     * To make sure that our file does not go unclosed after an error, we
     * must assign the FILE pointer before any further error can occur in
     * this routine.
     */
    if (file == stdin)
        file = get_binary_stdin_(); /* just to be safe */

    decoder->private_->file = file;

    return init_stream_internal_(
               decoder,
               file_read_callback_,
               decoder->private_->file == stdin ? 0 : file_seek_callback_,
               decoder->private_->file == stdin ? 0 : file_tell_callback_,
               decoder->private_->file == stdin ? 0 : file_length_callback_,
               file_eof_callback_,
               write_callback,
               metadata_callback,
               error_callback,
               client_data,
               is_ogg
               );
}

FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_FILE(
    FLAC__StreamDecoder* decoder,
    FILE* file,
    FLAC__StreamDecoderWriteCallback write_callback,
    FLAC__StreamDecoderMetadataCallback metadata_callback,
    FLAC__StreamDecoderErrorCallback error_callback,
    void* client_data
    )
{
    return init_FILE_internal_(decoder, file, write_callback, metadata_callback, error_callback, client_data, /*is_ogg=*/ false);
}

FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_ogg_FILE(
    FLAC__StreamDecoder* decoder,
    FILE* file,
    FLAC__StreamDecoderWriteCallback write_callback,
    FLAC__StreamDecoderMetadataCallback metadata_callback,
    FLAC__StreamDecoderErrorCallback error_callback,
    void* client_data
    )
{
    return init_FILE_internal_(decoder, file, write_callback, metadata_callback, error_callback, client_data, /*is_ogg=*/ true);
}

static FLAC__StreamDecoderInitStatus init_file_internal_(
    FLAC__StreamDecoder* decoder,
    const char* filename,
    FLAC__StreamDecoderWriteCallback write_callback,
    FLAC__StreamDecoderMetadataCallback metadata_callback,
    FLAC__StreamDecoderErrorCallback error_callback,
    void* client_data,
    FLAC__bool is_ogg
    )
{
    FILE* file;

    FLAC__ASSERT(0 != decoder);

    /*
     * To make sure that our file does not go unclosed after an error, we
     * have to do the same entrance checks here that are later performed
     * in FLAC__stream_decoder_init_FILE() before the FILE* is assigned.
     */
    if (decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
        return (FLAC__StreamDecoderInitStatus)(decoder->protected_->state = (FLAC__StreamDecoderState)FLAC__STREAM_DECODER_INIT_STATUS_ALREADY_INITIALIZED);

    if (0 == write_callback || 0 == error_callback)
        return (FLAC__StreamDecoderInitStatus)(decoder->protected_->state = (FLAC__StreamDecoderState)FLAC__STREAM_DECODER_INIT_STATUS_INVALID_CALLBACKS);

    file = filename ? fopen(filename, "rb") : stdin;

    if (0 == file)
        return FLAC__STREAM_DECODER_INIT_STATUS_ERROR_OPENING_FILE;

    return init_FILE_internal_(decoder, file, write_callback, metadata_callback, error_callback, client_data, is_ogg);
}

FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_file(
    FLAC__StreamDecoder* decoder,
    const char* filename,
    FLAC__StreamDecoderWriteCallback write_callback,
    FLAC__StreamDecoderMetadataCallback metadata_callback,
    FLAC__StreamDecoderErrorCallback error_callback,
    void* client_data
    )
{
    return init_file_internal_(decoder, filename, write_callback, metadata_callback, error_callback, client_data, /*is_ogg=*/ false);
}

FLAC_API FLAC__StreamDecoderInitStatus FLAC__stream_decoder_init_ogg_file(
    FLAC__StreamDecoder* decoder,
    const char* filename,
    FLAC__StreamDecoderWriteCallback write_callback,
    FLAC__StreamDecoderMetadataCallback metadata_callback,
    FLAC__StreamDecoderErrorCallback error_callback,
    void* client_data
    )
{
    return init_file_internal_(decoder, filename, write_callback, metadata_callback, error_callback, client_data, /*is_ogg=*/ true);
}

FLAC_API FLAC__bool FLAC__stream_decoder_finish(FLAC__StreamDecoder* decoder)
{
    FLAC__bool md5_failed = false;
    unsigned i;

    FLAC__ASSERT(0 != decoder);
    FLAC__ASSERT(0 != decoder->private_);
    FLAC__ASSERT(0 != decoder->protected_);

    if (decoder->protected_->state == FLAC__STREAM_DECODER_UNINITIALIZED)
        return true;

    /* see the comment in FLAC__seekable_stream_decoder_reset() as to why we
     * always call FLAC__MD5Final()
     */
    FLAC__MD5Final(decoder->private_->computed_md5sum, &decoder->private_->md5context);

    if (decoder->private_->has_seek_table && 0 != decoder->private_->seek_table.data.seek_table.points)
    {
        free(decoder->private_->seek_table.data.seek_table.points);
        decoder->private_->seek_table.data.seek_table.points = 0;
        decoder->private_->has_seek_table = false;
    }
    FLAC__bitreader_free(decoder->private_->input);
    for (i = 0; i < FLAC__MAX_CHANNELS; i++)
    {
        /* WATCHOUT:
         * FLAC__lpc_restore_signal_asm_ia32_mmx() requires that the
         * output arrays have a buffer of up to 3 zeroes in front
         * (at negative indices) for alignment purposes; we use 4
         * to keep the data well-aligned.
         */
        if (0 != decoder->private_->output[i])
        {
            free(decoder->private_->output[i] - 4);
            decoder->private_->output[i] = 0;
        }
        if (0 != decoder->private_->residual_unaligned[i])
        {
            free(decoder->private_->residual_unaligned[i]);
            decoder->private_->residual_unaligned[i] = decoder->private_->residual[i] = 0;
        }
    }
    decoder->private_->output_capacity = 0;
    decoder->private_->output_channels = 0;

    #if FLAC__HAS_OGG
    if (decoder->private_->is_ogg)
        FLAC__ogg_decoder_aspect_finish(&decoder->protected_->ogg_decoder_aspect);
    #endif

    if (0 != decoder->private_->file)
    {
        if (decoder->private_->file != stdin)
            fclose(decoder->private_->file);
        decoder->private_->file = 0;
    }

    if (decoder->private_->do_md5_checking)
    {
        if (memcmp(decoder->private_->stream_info.data.stream_info.md5sum, decoder->private_->computed_md5sum, 16))
            md5_failed = true;
    }
    decoder->private_->is_seeking = false;

    set_defaults_(decoder);

    decoder->protected_->state = FLAC__STREAM_DECODER_UNINITIALIZED;

    return !md5_failed;
}

FLAC_API FLAC__bool FLAC__stream_decoder_set_ogg_serial_number(FLAC__StreamDecoder* decoder, long value)
{
    FLAC__ASSERT(0 != decoder);
    FLAC__ASSERT(0 != decoder->private_);
    FLAC__ASSERT(0 != decoder->protected_);
    if (decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
        return false;
    #if FLAC__HAS_OGG
    /* can't check decoder->private_->is_ogg since that's not set until init time */
    FLAC__ogg_decoder_aspect_set_serial_number(&decoder->protected_->ogg_decoder_aspect, value);
    return true;
    #else
    ()value;
    return false;
    #endif
}

FLAC_API FLAC__bool FLAC__stream_decoder_set_md5_checking(FLAC__StreamDecoder* decoder, FLAC__bool value)
{
    FLAC__ASSERT(0 != decoder);
    FLAC__ASSERT(0 != decoder->protected_);
    if (decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
        return false;
    decoder->protected_->md5_checking = value;
    return true;
}

FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond(FLAC__StreamDecoder* decoder, FLAC__MetadataType type)
{
    FLAC__ASSERT(0 != decoder);
    FLAC__ASSERT(0 != decoder->private_);
    FLAC__ASSERT(0 != decoder->protected_);
    FLAC__ASSERT((unsigned)type <= FLAC__MAX_METADATA_TYPE_CODE);
    /* double protection */
    if ((unsigned)type > FLAC__MAX_METADATA_TYPE_CODE)
        return false;
    if (decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
        return false;
    decoder->private_->metadata_filter[type] = true;
    if (type == FLAC__METADATA_TYPE_APPLICATION)
        decoder->private_->metadata_filter_ids_count = 0;
    return true;
}

FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond_application(FLAC__StreamDecoder* decoder, const FLAC__byte id[4])
{
    FLAC__ASSERT(0 != decoder);
    FLAC__ASSERT(0 != decoder->private_);
    FLAC__ASSERT(0 != decoder->protected_);
    FLAC__ASSERT(0 != id);
    if (decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
        return false;

    if (decoder->private_->metadata_filter[FLAC__METADATA_TYPE_APPLICATION])
        return true;

    FLAC__ASSERT(0 != decoder->private_->metadata_filter_ids);

    if (decoder->private_->metadata_filter_ids_count == decoder->private_->metadata_filter_ids_capacity)
    {
        if (0 == (decoder->private_->metadata_filter_ids = (FLAC__byte*)safe_realloc_mul_2op_(decoder->private_->metadata_filter_ids, decoder->private_->metadata_filter_ids_capacity, /*times*/ 2)))
        {
            decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
            return false;
        }
        decoder->private_->metadata_filter_ids_capacity *= 2;
    }

    memcpy(decoder->private_->metadata_filter_ids + decoder->private_->metadata_filter_ids_count * (FLAC__STREAM_METADATA_APPLICATION_ID_LEN / 8), id, (FLAC__STREAM_METADATA_APPLICATION_ID_LEN / 8));
    decoder->private_->metadata_filter_ids_count++;

    return true;
}

FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_respond_all(FLAC__StreamDecoder* decoder)
{
    unsigned i;
    FLAC__ASSERT(0 != decoder);
    FLAC__ASSERT(0 != decoder->private_);
    FLAC__ASSERT(0 != decoder->protected_);
    if (decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
        return false;
    for (i = 0; i < sizeof(decoder->private_->metadata_filter) / sizeof(decoder->private_->metadata_filter[0]); i++)
        decoder->private_->metadata_filter[i] = true;
    decoder->private_->metadata_filter_ids_count = 0;
    return true;
}

FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore(FLAC__StreamDecoder* decoder, FLAC__MetadataType type)
{
    FLAC__ASSERT(0 != decoder);
    FLAC__ASSERT(0 != decoder->private_);
    FLAC__ASSERT(0 != decoder->protected_);
    FLAC__ASSERT((unsigned)type <= FLAC__MAX_METADATA_TYPE_CODE);
    /* double protection */
    if ((unsigned)type > FLAC__MAX_METADATA_TYPE_CODE)
        return false;
    if (decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
        return false;
    decoder->private_->metadata_filter[type] = false;
    if (type == FLAC__METADATA_TYPE_APPLICATION)
        decoder->private_->metadata_filter_ids_count = 0;
    return true;
}

FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore_application(FLAC__StreamDecoder* decoder, const FLAC__byte id[4])
{
    FLAC__ASSERT(0 != decoder);
    FLAC__ASSERT(0 != decoder->private_);
    FLAC__ASSERT(0 != decoder->protected_);
    FLAC__ASSERT(0 != id);
    if (decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
        return false;

    if (!decoder->private_->metadata_filter[FLAC__METADATA_TYPE_APPLICATION])
        return true;

    FLAC__ASSERT(0 != decoder->private_->metadata_filter_ids);

    if (decoder->private_->metadata_filter_ids_count == decoder->private_->metadata_filter_ids_capacity)
    {
        if (0 == (decoder->private_->metadata_filter_ids = (FLAC__byte*)safe_realloc_mul_2op_(decoder->private_->metadata_filter_ids, decoder->private_->metadata_filter_ids_capacity, /*times*/ 2)))
        {
            decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
            return false;
        }
        decoder->private_->metadata_filter_ids_capacity *= 2;
    }

    memcpy(decoder->private_->metadata_filter_ids + decoder->private_->metadata_filter_ids_count * (FLAC__STREAM_METADATA_APPLICATION_ID_LEN / 8), id, (FLAC__STREAM_METADATA_APPLICATION_ID_LEN / 8));
    decoder->private_->metadata_filter_ids_count++;

    return true;
}

FLAC_API FLAC__bool FLAC__stream_decoder_set_metadata_ignore_all(FLAC__StreamDecoder* decoder)
{
    FLAC__ASSERT(0 != decoder);
    FLAC__ASSERT(0 != decoder->private_);
    FLAC__ASSERT(0 != decoder->protected_);
    if (decoder->protected_->state != FLAC__STREAM_DECODER_UNINITIALIZED)
        return false;
    memset(decoder->private_->metadata_filter, 0, sizeof(decoder->private_->metadata_filter));
    decoder->private_->metadata_filter_ids_count = 0;
    return true;
}

FLAC_API FLAC__StreamDecoderState FLAC__stream_decoder_get_state(const FLAC__StreamDecoder* decoder)
{
    FLAC__ASSERT(0 != decoder);
    FLAC__ASSERT(0 != decoder->protected_);
    return decoder->protected_->state;
}

FLAC_API const char * FLAC__stream_decoder_get_resolved_state_string(const FLAC__StreamDecoder* decoder)
{
    return FLAC__StreamDecoderStateString[decoder->protected_->state];
}

FLAC_API FLAC__bool FLAC__stream_decoder_get_md5_checking(const FLAC__StreamDecoder* decoder)
{
    FLAC__ASSERT(0 != decoder);
    FLAC__ASSERT(0 != decoder->protected_);
    return decoder->protected_->md5_checking;
}

FLAC_API FLAC__uint64 FLAC__stream_decoder_get_total_samples(const FLAC__StreamDecoder* decoder)
{
    FLAC__ASSERT(0 != decoder);
    FLAC__ASSERT(0 != decoder->protected_);
    return decoder->private_->has_stream_info ? decoder->private_->stream_info.data.stream_info.total_samples : 0;
}

FLAC_API unsigned FLAC__stream_decoder_get_channels(const FLAC__StreamDecoder* decoder)
{
    FLAC__ASSERT(0 != decoder);
    FLAC__ASSERT(0 != decoder->protected_);
    return decoder->protected_->channels;
}

FLAC_API FLAC__ChannelAssignment FLAC__stream_decoder_get_channel_assignment(const FLAC__StreamDecoder* decoder)
{
    FLAC__ASSERT(0 != decoder);
    FLAC__ASSERT(0 != decoder->protected_);
    return decoder->protected_->channel_assignment;
}

FLAC_API unsigned FLAC__stream_decoder_get_bits_per_sample(const FLAC__StreamDecoder* decoder)
{
    FLAC__ASSERT(0 != decoder);
    FLAC__ASSERT(0 != decoder->protected_);
    return decoder->protected_->bits_per_sample;
}

FLAC_API unsigned FLAC__stream_decoder_get_sample_rate(const FLAC__StreamDecoder* decoder)
{
    FLAC__ASSERT(0 != decoder);
    FLAC__ASSERT(0 != decoder->protected_);
    return decoder->protected_->sample_rate;
}

FLAC_API unsigned FLAC__stream_decoder_get_blocksize(const FLAC__StreamDecoder* decoder)
{
    FLAC__ASSERT(0 != decoder);
    FLAC__ASSERT(0 != decoder->protected_);
    return decoder->protected_->blocksize;
}

FLAC_API FLAC__bool FLAC__stream_decoder_get_decode_position(const FLAC__StreamDecoder* decoder, FLAC__uint64* position)
{
    FLAC__ASSERT(0 != decoder);
    FLAC__ASSERT(0 != decoder->private_);
    FLAC__ASSERT(0 != position);

    #if FLAC__HAS_OGG
    if (decoder->private_->is_ogg)
        return false;
    #endif
    if (0 == decoder->private_->tell_callback)
        return false;
    if (decoder->private_->tell_callback(decoder, position, decoder->private_->client_data) != FLAC__STREAM_DECODER_TELL_STATUS_OK)
        return false;
    /* should never happen since all FLAC frames and metadata blocks are byte aligned, but check just in case */
    if (!FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input))
        return false;
    FLAC__ASSERT(*position >= FLAC__stream_decoder_get_input_bytes_unconsumed(decoder));
    *position -= FLAC__stream_decoder_get_input_bytes_unconsumed(decoder);
    return true;
}

FLAC_API FLAC__bool FLAC__stream_decoder_flush(FLAC__StreamDecoder* decoder)
{
    FLAC__ASSERT(0 != decoder);
    FLAC__ASSERT(0 != decoder->private_);
    FLAC__ASSERT(0 != decoder->protected_);

    decoder->private_->samples_decoded = 0;
    decoder->private_->do_md5_checking = false;

    #if FLAC__HAS_OGG
    if (decoder->private_->is_ogg)
        FLAC__ogg_decoder_aspect_flush(&decoder->protected_->ogg_decoder_aspect);
    #endif

    if (!FLAC__bitreader_clear(decoder->private_->input))
    {
        decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
        return false;
    }
    decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;

    return true;
}

FLAC_API FLAC__bool FLAC__stream_decoder_reset(FLAC__StreamDecoder* decoder)
{
    FLAC__ASSERT(0 != decoder);
    FLAC__ASSERT(0 != decoder->private_);
    FLAC__ASSERT(0 != decoder->protected_);

    if (!FLAC__stream_decoder_flush(decoder))
    {
        /* above call sets the state for us */
        return false;
    }

    #if FLAC__HAS_OGG
    /*@@@ could go in !internal_reset_hack block below */
    if (decoder->private_->is_ogg)
        FLAC__ogg_decoder_aspect_reset(&decoder->protected_->ogg_decoder_aspect);
    #endif

    /* Rewind if necessary.  If FLAC__stream_decoder_init() is calling us,
     * (internal_reset_hack) don't try to rewind since we are already at
     * the beginning of the stream and don't want to fail if the input is
     * not seekable.
     */
    if (!decoder->private_->internal_reset_hack)
    {
        if (decoder->private_->file == stdin)
            return false; /* can't rewind stdin, reset fails */
        if (decoder->private_->seek_callback && decoder->private_->seek_callback(decoder, 0, decoder->private_->client_data) == FLAC__STREAM_DECODER_SEEK_STATUS_ERROR)
            return false; /* seekable and seek fails, reset fails */
    }
    else
        decoder->private_->internal_reset_hack = false;

    decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_METADATA;

    decoder->private_->has_stream_info = false;
    if (decoder->private_->has_seek_table && 0 != decoder->private_->seek_table.data.seek_table.points)
    {
        free(decoder->private_->seek_table.data.seek_table.points);
        decoder->private_->seek_table.data.seek_table.points = 0;
        decoder->private_->has_seek_table = false;
    }
    decoder->private_->do_md5_checking = decoder->protected_->md5_checking;
    /*
     * This goes in reset() and not flush() because according to the spec, a
     * fixed-blocksize stream must stay that way through the whole stream.
     */
    decoder->private_->fixed_block_size = decoder->private_->next_fixed_block_size = 0;

    /* We initialize the FLAC__MD5Context even though we may never use it.  This
     * is because md5 checking may be turned on to start and then turned off if
     * a seek occurs.  So we init the context here and finalize it in
     * FLAC__stream_decoder_finish() to make sure things are always cleaned up
     * properly.
     */
    FLAC__MD5Init(&decoder->private_->md5context);

    decoder->private_->first_frame_offset = 0;
    decoder->private_->unparseable_frame_count = 0;

    return true;
}

FLAC_API FLAC__bool FLAC__stream_decoder_process_single(FLAC__StreamDecoder* decoder)
{
    FLAC__bool got_a_frame;
    FLAC__ASSERT(0 != decoder);
    FLAC__ASSERT(0 != decoder->protected_);

    while (1)
    {
        switch (decoder->protected_->state)
        {
            case FLAC__STREAM_DECODER_SEARCH_FOR_METADATA:
                if (!find_metadata_(decoder))
                    return false; /* above function sets the status for us */
                break;
            case FLAC__STREAM_DECODER_READ_METADATA:
                if (!read_metadata_(decoder))
                    return false; /* above function sets the status for us */
                else
                    return true;
            case FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC:
                if (!frame_sync_(decoder))
                    return true; /* above function sets the status for us */
                break;
            case FLAC__STREAM_DECODER_READ_FRAME:
                if (!read_frame_(decoder, &got_a_frame, /*do_full_decode=*/ true))
                    return false; /* above function sets the status for us */
                if (got_a_frame)
                    return true; /* above function sets the status for us */
                break;
            case FLAC__STREAM_DECODER_END_OF_STREAM:
            case FLAC__STREAM_DECODER_ABORTED:
                return true;
            default:
                FLAC__ASSERT(0);
                return false;
        }
    }
}

FLAC_API FLAC__bool FLAC__stream_decoder_process_until_end_of_metadata(FLAC__StreamDecoder* decoder)
{
    FLAC__ASSERT(0 != decoder);
    FLAC__ASSERT(0 != decoder->protected_);

    while (1)
    {
        switch (decoder->protected_->state)
        {
            case FLAC__STREAM_DECODER_SEARCH_FOR_METADATA:
                if (!find_metadata_(decoder))
                    return false; /* above function sets the status for us */
                break;
            case FLAC__STREAM_DECODER_READ_METADATA:
                if (!read_metadata_(decoder))
                    return false; /* above function sets the status for us */
                break;
            case FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC:
            case FLAC__STREAM_DECODER_READ_FRAME:
            case FLAC__STREAM_DECODER_END_OF_STREAM:
            case FLAC__STREAM_DECODER_ABORTED:
                return true;
            default:
                FLAC__ASSERT(0);
                return false;
        }
    }
}

FLAC_API FLAC__bool FLAC__stream_decoder_process_until_end_of_stream(FLAC__StreamDecoder* decoder)
{
    FLAC__bool dummy;
    FLAC__ASSERT(0 != decoder);
    FLAC__ASSERT(0 != decoder->protected_);

    while (1)
    {
        switch (decoder->protected_->state)
        {
            case FLAC__STREAM_DECODER_SEARCH_FOR_METADATA:
                if (!find_metadata_(decoder))
                    return false; /* above function sets the status for us */
                break;
            case FLAC__STREAM_DECODER_READ_METADATA:
                if (!read_metadata_(decoder))
                    return false; /* above function sets the status for us */
                break;
            case FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC:
                if (!frame_sync_(decoder))
                    return true; /* above function sets the status for us */
                break;
            case FLAC__STREAM_DECODER_READ_FRAME:
                if (!read_frame_(decoder, &dummy, /*do_full_decode=*/ true))
                    return false; /* above function sets the status for us */
                break;
            case FLAC__STREAM_DECODER_END_OF_STREAM:
            case FLAC__STREAM_DECODER_ABORTED:
                return true;
            default:
                FLAC__ASSERT(0);
                return false;
        }
    }
}

FLAC_API FLAC__bool FLAC__stream_decoder_skip_single_frame(FLAC__StreamDecoder* decoder)
{
    FLAC__bool got_a_frame;
    FLAC__ASSERT(0 != decoder);
    FLAC__ASSERT(0 != decoder->protected_);

    while (1)
    {
        switch (decoder->protected_->state)
        {
            case FLAC__STREAM_DECODER_SEARCH_FOR_METADATA:
            case FLAC__STREAM_DECODER_READ_METADATA:
                return false; /* above function sets the status for us */
            case FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC:
                if (!frame_sync_(decoder))
                    return true; /* above function sets the status for us */
                break;
            case FLAC__STREAM_DECODER_READ_FRAME:
                if (!read_frame_(decoder, &got_a_frame, /*do_full_decode=*/ false))
                    return false; /* above function sets the status for us */
                if (got_a_frame)
                    return true; /* above function sets the status for us */
                break;
            case FLAC__STREAM_DECODER_END_OF_STREAM:
            case FLAC__STREAM_DECODER_ABORTED:
                return true;
            default:
                FLAC__ASSERT(0);
                return false;
        }
    }
}

FLAC_API FLAC__bool FLAC__stream_decoder_seek_absolute(FLAC__StreamDecoder* decoder, FLAC__uint64 sample)
{
    FLAC__uint64 length;

    FLAC__ASSERT(0 != decoder);

    if (
        decoder->protected_->state != FLAC__STREAM_DECODER_SEARCH_FOR_METADATA &&
        decoder->protected_->state != FLAC__STREAM_DECODER_READ_METADATA &&
        decoder->protected_->state != FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC &&
        decoder->protected_->state != FLAC__STREAM_DECODER_READ_FRAME &&
        decoder->protected_->state != FLAC__STREAM_DECODER_END_OF_STREAM
        )
        return false;

    if (0 == decoder->private_->seek_callback)
        return false;

    FLAC__ASSERT(decoder->private_->seek_callback);
    FLAC__ASSERT(decoder->private_->tell_callback);
    FLAC__ASSERT(decoder->private_->length_callback);
    FLAC__ASSERT(decoder->private_->eof_callback);

    if (FLAC__stream_decoder_get_total_samples(decoder) > 0 && sample >= FLAC__stream_decoder_get_total_samples(decoder))
        return false;

    decoder->private_->is_seeking = true;

    /* turn off md5 checking if a seek is attempted */
    decoder->private_->do_md5_checking = false;

    /* get the file length (currently our algorithm needs to know the length so it's also an error to get FLAC__STREAM_DECODER_LENGTH_STATUS_UNSUPPORTED) */
    if (decoder->private_->length_callback(decoder, &length, decoder->private_->client_data) != FLAC__STREAM_DECODER_LENGTH_STATUS_OK)
    {
        decoder->private_->is_seeking = false;
        return false;
    }

    /* if we haven't finished processing the metadata yet, do that so we have the STREAMINFO, SEEK_TABLE, and first_frame_offset */
    if (
        decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_METADATA ||
        decoder->protected_->state == FLAC__STREAM_DECODER_READ_METADATA
        )
    {
        if (!FLAC__stream_decoder_process_until_end_of_metadata(decoder))
        {
            /* above call sets the state for us */
            decoder->private_->is_seeking = false;
            return false;
        }
        /* check this again in case we didn't know total_samples the first time */
        if (FLAC__stream_decoder_get_total_samples(decoder) > 0 && sample >= FLAC__stream_decoder_get_total_samples(decoder))
        {
            decoder->private_->is_seeking = false;
            return false;
        }
    }

    {
        const FLAC__bool ok =
            #if FLAC__HAS_OGG
            decoder->private_->is_ogg ?
            seek_to_absolute_sample_ogg_(decoder, length, sample) :
            #endif
            seek_to_absolute_sample_(decoder, length, sample)
        ;
        decoder->private_->is_seeking = false;
        return ok;
    }
}

/***********************************************************************
*
* Protected class methods
*
***********************************************************************/

unsigned FLAC__stream_decoder_get_input_bytes_unconsumed(const FLAC__StreamDecoder* decoder)
{
    FLAC__ASSERT(0 != decoder);
    FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));
    FLAC__ASSERT(!(FLAC__bitreader_get_input_bits_unconsumed(decoder->private_->input) & 7));
    return FLAC__bitreader_get_input_bits_unconsumed(decoder->private_->input) / 8;
}

/***********************************************************************
*
* Private class methods
*
***********************************************************************/

void set_defaults_(FLAC__StreamDecoder* decoder)
{
    #if FLAC__HAS_OGG
    decoder->private_->is_ogg = false;
    #endif
    decoder->private_->read_callback = 0;
    decoder->private_->seek_callback = 0;
    decoder->private_->tell_callback = 0;
    decoder->private_->length_callback = 0;
    decoder->private_->eof_callback = 0;
    decoder->private_->write_callback = 0;
    decoder->private_->metadata_callback = 0;
    decoder->private_->error_callback = 0;
    decoder->private_->client_data = 0;

    memset(decoder->private_->metadata_filter, 0, sizeof(decoder->private_->metadata_filter));
    decoder->private_->metadata_filter[FLAC__METADATA_TYPE_STREAMINFO] = true;
    decoder->private_->metadata_filter_ids_count = 0;

    decoder->protected_->md5_checking = false;

    #if FLAC__HAS_OGG
    FLAC__ogg_decoder_aspect_set_defaults(&decoder->protected_->ogg_decoder_aspect);
    #endif
}

/*
 * This will forcibly set stdin to binary mode (for OSes that require it)
 */
FILE * get_binary_stdin_()
{
    /* if something breaks here it is probably due to the presence or
     * absence of an underscore before the identifiers 'setmode',
     * 'fileno', and/or 'O_BINARY'; check your system header files.
     */
    #if defined _MSC_VER || defined __MINGW32__
    _setmode(_fileno(stdin), _O_BINARY);
    #elif defined __CYGWIN__
    /* almost certainly not needed for any modern Cygwin, but let's be safe... */
    setmode(_fileno(stdin), _O_BINARY);
    #elif defined __EMX__
    setmode(fileno(stdin), O_BINARY);
    #endif

    return stdin;
}

FLAC__bool allocate_output_(FLAC__StreamDecoder* decoder, unsigned size, unsigned channels)
{
    unsigned i;
    FLAC__int32* tmp;

    if (size <= decoder->private_->output_capacity && channels <= decoder->private_->output_channels)
        return true;

    /* simply using realloc() is not practical because the number of channels may change mid-stream */

    for (i = 0; i < FLAC__MAX_CHANNELS; i++)
    {
        if (0 != decoder->private_->output[i])
        {
            free(decoder->private_->output[i] - 4);
            decoder->private_->output[i] = 0;
        }
        if (0 != decoder->private_->residual_unaligned[i])
        {
            free(decoder->private_->residual_unaligned[i]);
            decoder->private_->residual_unaligned[i] = decoder->private_->residual[i] = 0;
        }
    }

    for (i = 0; i < channels; i++)
    {
        /* WATCHOUT:
         * FLAC__lpc_restore_signal_asm_ia32_mmx() requires that the
         * output arrays have a buffer of up to 3 zeroes in front
         * (at negative indices) for alignment purposes; we use 4
         * to keep the data well-aligned.
         */
        tmp = (FLAC__int32*)safe_malloc_muladd2_(sizeof(FLAC__int32), /*times (*/ size, /*+*/ 4 /*)*/);
        if (tmp == 0)
        {
            decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
            return false;
        }
        memset(tmp, 0, sizeof(FLAC__int32) * 4);
        decoder->private_->output[i] = tmp + 4;

        /* WATCHOUT:
         * minimum of quadword alignment for PPC vector optimizations is REQUIRED:
         */
        if (!FLAC__memory_alloc_aligned_int32_array(size, &decoder->private_->residual_unaligned[i], &decoder->private_->residual[i]))
        {
            decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
            return false;
        }
    }

    decoder->private_->output_capacity = size;
    decoder->private_->output_channels = channels;

    return true;
}

FLAC__bool has_id_filtered_(FLAC__StreamDecoder* decoder, FLAC__byte* id)
{
    size_t i;

    FLAC__ASSERT(0 != decoder);
    FLAC__ASSERT(0 != decoder->private_);

    for (i = 0; i < decoder->private_->metadata_filter_ids_count; i++)
        if (0 == memcmp(decoder->private_->metadata_filter_ids + i * (FLAC__STREAM_METADATA_APPLICATION_ID_LEN / 8), id, (FLAC__STREAM_METADATA_APPLICATION_ID_LEN / 8)))
            return true;

    return false;
}

FLAC__bool find_metadata_(FLAC__StreamDecoder* decoder)
{
    FLAC__uint32 x;
    unsigned i, id;
    FLAC__bool first = true;

    FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));

    for (i = id = 0; i < 4;)
    {
        if (decoder->private_->cached)
        {
            x = (FLAC__uint32)decoder->private_->lookahead;
            decoder->private_->cached = false;
        }
        else
        {
            if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
                return false; /* read_callback_ sets the state for us */
        }
        if (x == FLAC__STREAM_SYNC_STRING[i])
        {
            first = true;
            i++;
            id = 0;
            continue;
        }
        if (x == ID3V2_TAG_[id])
        {
            id++;
            i = 0;
            if (id == 3)
            {
                if (!skip_id3v2_tag_(decoder))
                    return false; /* skip_id3v2_tag_ sets the state for us */
            }
            continue;
        }
        id = 0;
        if (x == 0xff)   /* MAGIC NUMBER for the first 8 frame sync bits */
        {
            decoder->private_->header_warmup[0] = (FLAC__byte)x;
            if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
                return false; /* read_callback_ sets the state for us */

            /* we have to check if we just read two 0xff's in a row; the second may actually be the beginning of the sync code */
            /* else we have to check if the second byte is the end of a sync code */
            if (x == 0xff)   /* MAGIC NUMBER for the first 8 frame sync bits */
            {
                decoder->private_->lookahead = (FLAC__byte)x;
                decoder->private_->cached = true;
            }
            else if (x >> 2 == 0x3e)   /* MAGIC NUMBER for the last 6 sync bits */
            {
                decoder->private_->header_warmup[1] = (FLAC__byte)x;
                decoder->protected_->state = FLAC__STREAM_DECODER_READ_FRAME;
                return true;
            }
        }
        i = 0;
        if (first)
        {
            send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
            first = false;
        }
    }

    decoder->protected_->state = FLAC__STREAM_DECODER_READ_METADATA;
    return true;
}

FLAC__bool read_metadata_(FLAC__StreamDecoder* decoder)
{
    FLAC__bool is_last;
    FLAC__uint32 i, x, type, length;

    FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));

    if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_IS_LAST_LEN))
        return false; /* read_callback_ sets the state for us */
    is_last = x ? true : false;

    if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &type, FLAC__STREAM_METADATA_TYPE_LEN))
        return false; /* read_callback_ sets the state for us */

    if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &length, FLAC__STREAM_METADATA_LENGTH_LEN))
        return false; /* read_callback_ sets the state for us */

    if (type == FLAC__METADATA_TYPE_STREAMINFO)
    {
        if (!read_metadata_streaminfo_(decoder, is_last, length))
            return false;

        decoder->private_->has_stream_info = true;
        if (0 == memcmp(decoder->private_->stream_info.data.stream_info.md5sum, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0", 16))
            decoder->private_->do_md5_checking = false;
        if (!decoder->private_->is_seeking && decoder->private_->metadata_filter[FLAC__METADATA_TYPE_STREAMINFO] && decoder->private_->metadata_callback)
            decoder->private_->metadata_callback(decoder, &decoder->private_->stream_info, decoder->private_->client_data);
    }
    else if (type == FLAC__METADATA_TYPE_SEEKTABLE)
    {
        if (!read_metadata_seektable_(decoder, is_last, length))
            return false;

        decoder->private_->has_seek_table = true;
        if (!decoder->private_->is_seeking && decoder->private_->metadata_filter[FLAC__METADATA_TYPE_SEEKTABLE] && decoder->private_->metadata_callback)
            decoder->private_->metadata_callback(decoder, &decoder->private_->seek_table, decoder->private_->client_data);
    }
    else
    {
        FLAC__bool skip_it = !decoder->private_->metadata_filter[type];
        unsigned real_length = length;
        FLAC__StreamMetadata block;

        block.is_last = is_last;
        block.type = (FLAC__MetadataType)type;
        block.length = length;

        if (type == FLAC__METADATA_TYPE_APPLICATION)
        {
            if (!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, block.data.application.id, FLAC__STREAM_METADATA_APPLICATION_ID_LEN / 8))
                return false; /* read_callback_ sets the state for us */

            if (real_length < FLAC__STREAM_METADATA_APPLICATION_ID_LEN / 8)   /* underflow check */
            {
                decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR; /*@@@@@@ maybe wrong error? need to resync?*/
                return false;
            }

            real_length -= FLAC__STREAM_METADATA_APPLICATION_ID_LEN / 8;

            if (decoder->private_->metadata_filter_ids_count > 0 && has_id_filtered_(decoder, block.data.application.id))
                skip_it = !skip_it;
        }

        if (skip_it)
        {
            if (!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, real_length))
                return false; /* read_callback_ sets the state for us */
        }
        else
        {
            switch (type)
            {
                case FLAC__METADATA_TYPE_PADDING:
                    /* skip the padding bytes */
                    if (!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, real_length))
                        return false; /* read_callback_ sets the state for us */
                    break;
                case FLAC__METADATA_TYPE_APPLICATION:
                    /* remember, we read the ID already */
                    if (real_length > 0)
                    {
                        if (0 == (block.data.application.data = (FLAC__byte*)malloc(real_length)))
                        {
                            decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
                            return false;
                        }
                        if (!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, block.data.application.data, real_length))
                            return false; /* read_callback_ sets the state for us */
                    }
                    else
                        block.data.application.data = 0;
                    break;
                case FLAC__METADATA_TYPE_VORBIS_COMMENT:
                    if (!read_metadata_vorbiscomment_(decoder, &block.data.vorbis_comment))
                        return false;
                    break;
                case FLAC__METADATA_TYPE_CUESHEET:
                    if (!read_metadata_cuesheet_(decoder, &block.data.cue_sheet))
                        return false;
                    break;
                case FLAC__METADATA_TYPE_PICTURE:
                    if (!read_metadata_picture_(decoder, &block.data.picture))
                        return false;
                    break;
                case FLAC__METADATA_TYPE_STREAMINFO:
                case FLAC__METADATA_TYPE_SEEKTABLE:
                    FLAC__ASSERT(0);
                    break;
                default:
                    if (real_length > 0)
                    {
                        if (0 == (block.data.unknown.data = (FLAC__byte*)malloc(real_length)))
                        {
                            decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
                            return false;
                        }
                        if (!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, block.data.unknown.data, real_length))
                            return false; /* read_callback_ sets the state for us */
                    }
                    else
                        block.data.unknown.data = 0;
                    break;
            }
            if (!decoder->private_->is_seeking && decoder->private_->metadata_callback)
                decoder->private_->metadata_callback(decoder, &block, decoder->private_->client_data);

            /* now we have to free any malloc()ed data in the block */
            switch (type)
            {
                case FLAC__METADATA_TYPE_PADDING:
                    break;
                case FLAC__METADATA_TYPE_APPLICATION:
                    if (0 != block.data.application.data)
                        free(block.data.application.data);
                    break;
                case FLAC__METADATA_TYPE_VORBIS_COMMENT:
                    if (0 != block.data.vorbis_comment.vendor_string.entry)
                        free(block.data.vorbis_comment.vendor_string.entry);
                    if (block.data.vorbis_comment.num_comments > 0)
                        for (i = 0; i < block.data.vorbis_comment.num_comments; i++)
                            if (0 != block.data.vorbis_comment.comments[i].entry)
                                free(block.data.vorbis_comment.comments[i].entry);
                    if (0 != block.data.vorbis_comment.comments)
                        free(block.data.vorbis_comment.comments);
                    break;
                case FLAC__METADATA_TYPE_CUESHEET:
                    if (block.data.cue_sheet.num_tracks > 0)
                        for (i = 0; i < block.data.cue_sheet.num_tracks; i++)
                            if (0 != block.data.cue_sheet.tracks[i].indices)
                                free(block.data.cue_sheet.tracks[i].indices);
                    if (0 != block.data.cue_sheet.tracks)
                        free(block.data.cue_sheet.tracks);
                    break;
                case FLAC__METADATA_TYPE_PICTURE:
                    if (0 != block.data.picture.mime_type)
                        free(block.data.picture.mime_type);
                    if (0 != block.data.picture.description)
                        free(block.data.picture.description);
                    if (0 != block.data.picture.data)
                        free(block.data.picture.data);
                    break;
                case FLAC__METADATA_TYPE_STREAMINFO:
                case FLAC__METADATA_TYPE_SEEKTABLE:
                    FLAC__ASSERT(0);
                default:
                    if (0 != block.data.unknown.data)
                        free(block.data.unknown.data);
                    break;
            }
        }
    }

    if (is_last)
    {
        /* if this fails, it's OK, it's just a hint for the seek routine */
        if (!FLAC__stream_decoder_get_decode_position(decoder, &decoder->private_->first_frame_offset))
            decoder->private_->first_frame_offset = 0;
        decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
    }

    return true;
}

FLAC__bool read_metadata_streaminfo_(FLAC__StreamDecoder* decoder, FLAC__bool is_last, unsigned length)
{
    FLAC__uint32 x;
    unsigned bits, used_bits = 0;

    FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));

    decoder->private_->stream_info.type = FLAC__METADATA_TYPE_STREAMINFO;
    decoder->private_->stream_info.is_last = is_last;
    decoder->private_->stream_info.length = length;

    bits = FLAC__STREAM_METADATA_STREAMINFO_MIN_BLOCK_SIZE_LEN;
    if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, bits))
        return false; /* read_callback_ sets the state for us */
    decoder->private_->stream_info.data.stream_info.min_blocksize = x;
    used_bits += bits;

    bits = FLAC__STREAM_METADATA_STREAMINFO_MAX_BLOCK_SIZE_LEN;
    if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_MAX_BLOCK_SIZE_LEN))
        return false; /* read_callback_ sets the state for us */
    decoder->private_->stream_info.data.stream_info.max_blocksize = x;
    used_bits += bits;

    bits = FLAC__STREAM_METADATA_STREAMINFO_MIN_FRAME_SIZE_LEN;
    if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_MIN_FRAME_SIZE_LEN))
        return false; /* read_callback_ sets the state for us */
    decoder->private_->stream_info.data.stream_info.min_framesize = x;
    used_bits += bits;

    bits = FLAC__STREAM_METADATA_STREAMINFO_MAX_FRAME_SIZE_LEN;
    if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_MAX_FRAME_SIZE_LEN))
        return false; /* read_callback_ sets the state for us */
    decoder->private_->stream_info.data.stream_info.max_framesize = x;
    used_bits += bits;

    bits = FLAC__STREAM_METADATA_STREAMINFO_SAMPLE_RATE_LEN;
    if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_SAMPLE_RATE_LEN))
        return false; /* read_callback_ sets the state for us */
    decoder->private_->stream_info.data.stream_info.sample_rate = x;
    used_bits += bits;

    bits = FLAC__STREAM_METADATA_STREAMINFO_CHANNELS_LEN;
    if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_CHANNELS_LEN))
        return false; /* read_callback_ sets the state for us */
    decoder->private_->stream_info.data.stream_info.channels = x + 1;
    used_bits += bits;

    bits = FLAC__STREAM_METADATA_STREAMINFO_BITS_PER_SAMPLE_LEN;
    if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_BITS_PER_SAMPLE_LEN))
        return false; /* read_callback_ sets the state for us */
    decoder->private_->stream_info.data.stream_info.bits_per_sample = x + 1;
    used_bits += bits;

    bits = FLAC__STREAM_METADATA_STREAMINFO_TOTAL_SAMPLES_LEN;
    if (!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &decoder->private_->stream_info.data.stream_info.total_samples, FLAC__STREAM_METADATA_STREAMINFO_TOTAL_SAMPLES_LEN))
        return false; /* read_callback_ sets the state for us */
    used_bits += bits;

    if (!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, decoder->private_->stream_info.data.stream_info.md5sum, 16))
        return false; /* read_callback_ sets the state for us */
    used_bits += 16 * 8;

    /* skip the rest of the block */
    FLAC__ASSERT(used_bits % 8 == 0);
    length -= (used_bits / 8);
    if (!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, length))
        return false; /* read_callback_ sets the state for us */

    return true;
}

FLAC__bool read_metadata_seektable_(FLAC__StreamDecoder* decoder, FLAC__bool is_last, unsigned length)
{
    FLAC__uint32 i, x;
    FLAC__uint64 xx;

    FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));

    decoder->private_->seek_table.type = FLAC__METADATA_TYPE_SEEKTABLE;
    decoder->private_->seek_table.is_last = is_last;
    decoder->private_->seek_table.length = length;

    decoder->private_->seek_table.data.seek_table.num_points = length / FLAC__STREAM_METADATA_SEEKPOINT_LENGTH;

    /* use realloc since we may pass through here several times (e.g. after seeking) */
    if (0 == (decoder->private_->seek_table.data.seek_table.points = (FLAC__StreamMetadata_SeekPoint*)safe_realloc_mul_2op_(decoder->private_->seek_table.data.seek_table.points, decoder->private_->seek_table.data.seek_table.num_points, /*times*/ sizeof(FLAC__StreamMetadata_SeekPoint))))
    {
        decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
        return false;
    }
    for (i = 0; i < decoder->private_->seek_table.data.seek_table.num_points; i++)
    {
        if (!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &xx, FLAC__STREAM_METADATA_SEEKPOINT_SAMPLE_NUMBER_LEN))
            return false; /* read_callback_ sets the state for us */
        decoder->private_->seek_table.data.seek_table.points[i].sample_number = xx;

        if (!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &xx, FLAC__STREAM_METADATA_SEEKPOINT_STREAM_OFFSET_LEN))
            return false; /* read_callback_ sets the state for us */
        decoder->private_->seek_table.data.seek_table.points[i].stream_offset = xx;

        if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_SEEKPOINT_FRAME_SAMPLES_LEN))
            return false; /* read_callback_ sets the state for us */
        decoder->private_->seek_table.data.seek_table.points[i].frame_samples = x;
    }
    length -= (decoder->private_->seek_table.data.seek_table.num_points * FLAC__STREAM_METADATA_SEEKPOINT_LENGTH);
    /* if there is a partial point left, skip over it */
    if (length > 0)
    {
        /*@@@ do a send_error_to_client_() here?  there's an argument for either way */
        if (!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, length))
            return false; /* read_callback_ sets the state for us */
    }

    return true;
}

FLAC__bool read_metadata_vorbiscomment_(FLAC__StreamDecoder* decoder, FLAC__StreamMetadata_VorbisComment* obj)
{
    FLAC__uint32 i;

    FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));

    /* read vendor string */
    FLAC__ASSERT(FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN == 32);
    if (!FLAC__bitreader_read_uint32_little_endian(decoder->private_->input, &obj->vendor_string.length))
        return false; /* read_callback_ sets the state for us */
    if (obj->vendor_string.length > 0)
    {
        if (0 == (obj->vendor_string.entry = (FLAC__byte*)safe_malloc_add_2op_(obj->vendor_string.length, /*+*/ 1)))
        {
            decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
            return false;
        }
        if (!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, obj->vendor_string.entry, obj->vendor_string.length))
            return false; /* read_callback_ sets the state for us */
        obj->vendor_string.entry[obj->vendor_string.length] = '\0';
    }
    else
        obj->vendor_string.entry = 0;

    /* read num comments */
    FLAC__ASSERT(FLAC__STREAM_METADATA_VORBIS_COMMENT_NUM_COMMENTS_LEN == 32);
    if (!FLAC__bitreader_read_uint32_little_endian(decoder->private_->input, &obj->num_comments))
        return false; /* read_callback_ sets the state for us */

    /* read comments */
    if (obj->num_comments > 0)
    {
        if (0 == (obj->comments = (FLAC__StreamMetadata_VorbisComment_Entry*)safe_malloc_mul_2op_(obj->num_comments, /*times*/ sizeof(FLAC__StreamMetadata_VorbisComment_Entry))))
        {
            decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
            return false;
        }
        for (i = 0; i < obj->num_comments; i++)
        {
            FLAC__ASSERT(FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN == 32);
            if (!FLAC__bitreader_read_uint32_little_endian(decoder->private_->input, &obj->comments[i].length))
                return false; /* read_callback_ sets the state for us */
            if (obj->comments[i].length > 0)
            {
                if (0 == (obj->comments[i].entry = (FLAC__byte*)safe_malloc_add_2op_(obj->comments[i].length, /*+*/ 1)))
                {
                    decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
                    return false;
                }
                if (!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, obj->comments[i].entry, obj->comments[i].length))
                    return false; /* read_callback_ sets the state for us */
                obj->comments[i].entry[obj->comments[i].length] = '\0';
            }
            else
                obj->comments[i].entry = 0;
        }
    }
    else
    {
        obj->comments = 0;
    }

    return true;
}

FLAC__bool read_metadata_cuesheet_(FLAC__StreamDecoder* decoder, FLAC__StreamMetadata_CueSheet* obj)
{
    FLAC__uint32 i, j, x;

    FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));

    memset(obj, 0, sizeof(FLAC__StreamMetadata_CueSheet));

    FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_MEDIA_CATALOG_NUMBER_LEN % 8 == 0);
    if (!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, (FLAC__byte*)obj->media_catalog_number, FLAC__STREAM_METADATA_CUESHEET_MEDIA_CATALOG_NUMBER_LEN / 8))
        return false; /* read_callback_ sets the state for us */

    if (!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &obj->lead_in, FLAC__STREAM_METADATA_CUESHEET_LEAD_IN_LEN))
        return false; /* read_callback_ sets the state for us */

    if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_IS_CD_LEN))
        return false; /* read_callback_ sets the state for us */
    obj->is_cd = x ? true : false;

    if (!FLAC__bitreader_skip_bits_no_crc(decoder->private_->input, FLAC__STREAM_METADATA_CUESHEET_RESERVED_LEN))
        return false; /* read_callback_ sets the state for us */

    if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_NUM_TRACKS_LEN))
        return false; /* read_callback_ sets the state for us */
    obj->num_tracks = x;

    if (obj->num_tracks > 0)
    {
        if (0 == (obj->tracks = (FLAC__StreamMetadata_CueSheet_Track*)safe_calloc_(obj->num_tracks, sizeof(FLAC__StreamMetadata_CueSheet_Track))))
        {
            decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
            return false;
        }
        for (i = 0; i < obj->num_tracks; i++)
        {
            FLAC__StreamMetadata_CueSheet_Track* track = &obj->tracks[i];
            if (!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &track->offset, FLAC__STREAM_METADATA_CUESHEET_TRACK_OFFSET_LEN))
                return false; /* read_callback_ sets the state for us */

            if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_TRACK_NUMBER_LEN))
                return false; /* read_callback_ sets the state for us */
            track->number = (FLAC__byte)x;

            FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_TRACK_ISRC_LEN % 8 == 0);
            if (!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, (FLAC__byte*)track->isrc, FLAC__STREAM_METADATA_CUESHEET_TRACK_ISRC_LEN / 8))
                return false; /* read_callback_ sets the state for us */

            if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_TRACK_TYPE_LEN))
                return false; /* read_callback_ sets the state for us */
            track->type = x;

            if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_TRACK_PRE_EMPHASIS_LEN))
                return false; /* read_callback_ sets the state for us */
            track->pre_emphasis = x;

            if (!FLAC__bitreader_skip_bits_no_crc(decoder->private_->input, FLAC__STREAM_METADATA_CUESHEET_TRACK_RESERVED_LEN))
                return false; /* read_callback_ sets the state for us */

            if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_TRACK_NUM_INDICES_LEN))
                return false; /* read_callback_ sets the state for us */
            track->num_indices = (FLAC__byte)x;

            if (track->num_indices > 0)
            {
                if (0 == (track->indices = (FLAC__StreamMetadata_CueSheet_Index*)safe_calloc_(track->num_indices, sizeof(FLAC__StreamMetadata_CueSheet_Index))))
                {
                    decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
                    return false;
                }
                for (j = 0; j < track->num_indices; j++)
                {
                    FLAC__StreamMetadata_CueSheet_Index* index = &track->indices[j];
                    if (!FLAC__bitreader_read_raw_uint64(decoder->private_->input, &index->offset, FLAC__STREAM_METADATA_CUESHEET_INDEX_OFFSET_LEN))
                        return false; /* read_callback_ sets the state for us */

                    if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_INDEX_NUMBER_LEN))
                        return false; /* read_callback_ sets the state for us */
                    index->number = (FLAC__byte)x;

                    if (!FLAC__bitreader_skip_bits_no_crc(decoder->private_->input, FLAC__STREAM_METADATA_CUESHEET_INDEX_RESERVED_LEN))
                        return false; /* read_callback_ sets the state for us */
                }
            }
        }
    }

    return true;
}

FLAC__bool read_metadata_picture_(FLAC__StreamDecoder* decoder, FLAC__StreamMetadata_Picture* obj)
{
    FLAC__uint32 x;

    FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));

    /* read type */
    if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_PICTURE_TYPE_LEN))
        return false; /* read_callback_ sets the state for us */
    obj->type = (FLAC__StreamMetadata_Picture_Type)x;

    /* read MIME type */
    if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_PICTURE_MIME_TYPE_LENGTH_LEN))
        return false; /* read_callback_ sets the state for us */
    if (0 == (obj->mime_type = (char*)safe_malloc_add_2op_(x, /*+*/ 1)))
    {
        decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
        return false;
    }
    if (x > 0)
    {
        if (!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, (FLAC__byte*)obj->mime_type, x))
            return false; /* read_callback_ sets the state for us */
    }
    obj->mime_type[x] = '\0';

    /* read description */
    if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_PICTURE_DESCRIPTION_LENGTH_LEN))
        return false; /* read_callback_ sets the state for us */
    if (0 == (obj->description = (FLAC__byte*)safe_malloc_add_2op_(x, /*+*/ 1)))
    {
        decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
        return false;
    }
    if (x > 0)
    {
        if (!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, obj->description, x))
            return false; /* read_callback_ sets the state for us */
    }
    obj->description[x] = '\0';

    /* read width */
    if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &obj->width, FLAC__STREAM_METADATA_PICTURE_WIDTH_LEN))
        return false; /* read_callback_ sets the state for us */

    /* read height */
    if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &obj->height, FLAC__STREAM_METADATA_PICTURE_HEIGHT_LEN))
        return false; /* read_callback_ sets the state for us */

    /* read depth */
    if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &obj->depth, FLAC__STREAM_METADATA_PICTURE_DEPTH_LEN))
        return false; /* read_callback_ sets the state for us */

    /* read colors */
    if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &obj->colors, FLAC__STREAM_METADATA_PICTURE_COLORS_LEN))
        return false; /* read_callback_ sets the state for us */

    /* read data */
    if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &(obj->data_length), FLAC__STREAM_METADATA_PICTURE_DATA_LENGTH_LEN))
        return false; /* read_callback_ sets the state for us */
    if (0 == (obj->data = (FLAC__byte*)safe_malloc_(obj->data_length)))
    {
        decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
        return false;
    }
    if (obj->data_length > 0)
    {
        if (!FLAC__bitreader_read_byte_block_aligned_no_crc(decoder->private_->input, obj->data, obj->data_length))
            return false; /* read_callback_ sets the state for us */
    }

    return true;
}

FLAC__bool skip_id3v2_tag_(FLAC__StreamDecoder* decoder)
{
    FLAC__uint32 x;
    unsigned i, skip;

    /* skip the version and flags bytes */
    if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 24))
        return false; /* read_callback_ sets the state for us */
    /* get the size (in bytes) to skip */
    skip = 0;
    for (i = 0; i < 4; i++)
    {
        if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
            return false; /* read_callback_ sets the state for us */
        skip <<= 7;
        skip |= (x & 0x7f);
    }
    /* skip the rest of the tag */
    if (!FLAC__bitreader_skip_byte_block_aligned_no_crc(decoder->private_->input, skip))
        return false; /* read_callback_ sets the state for us */
    return true;
}

FLAC__bool frame_sync_(FLAC__StreamDecoder* decoder)
{
    FLAC__uint32 x;
    FLAC__bool first = true;

    /* If we know the total number of samples in the stream, stop if we've read that many. */
    /* This will stop us, for example, from wasting time trying to sync on an ID3V1 tag. */
    if (FLAC__stream_decoder_get_total_samples(decoder) > 0)
    {
        if (decoder->private_->samples_decoded >= FLAC__stream_decoder_get_total_samples(decoder))
        {
            decoder->protected_->state = FLAC__STREAM_DECODER_END_OF_STREAM;
            return true;
        }
    }

    /* make sure we're byte aligned */
    if (!FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input))
    {
        if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__bitreader_bits_left_for_byte_alignment(decoder->private_->input)))
            return false; /* read_callback_ sets the state for us */
    }

    while (1)
    {
        if (decoder->private_->cached)
        {
            x = (FLAC__uint32)decoder->private_->lookahead;
            decoder->private_->cached = false;
        }
        else
        {
            if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
                return false; /* read_callback_ sets the state for us */
        }
        if (x == 0xff)   /* MAGIC NUMBER for the first 8 frame sync bits */
        {
            decoder->private_->header_warmup[0] = (FLAC__byte)x;
            if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
                return false; /* read_callback_ sets the state for us */

            /* we have to check if we just read two 0xff's in a row; the second may actually be the beginning of the sync code */
            /* else we have to check if the second byte is the end of a sync code */
            if (x == 0xff)   /* MAGIC NUMBER for the first 8 frame sync bits */
            {
                decoder->private_->lookahead = (FLAC__byte)x;
                decoder->private_->cached = true;
            }
            else if (x >> 2 == 0x3e)   /* MAGIC NUMBER for the last 6 sync bits */
            {
                decoder->private_->header_warmup[1] = (FLAC__byte)x;
                decoder->protected_->state = FLAC__STREAM_DECODER_READ_FRAME;
                return true;
            }
        }
        if (first)
        {
            send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
            first = false;
        }
    }

    return true;
}

FLAC__bool read_frame_(FLAC__StreamDecoder* decoder, FLAC__bool* got_a_frame, FLAC__bool do_full_decode)
{
    unsigned channel;
    unsigned i;
    FLAC__int32 mid, side;
    unsigned frame_crc; /* the one we calculate from the input stream */
    FLAC__uint32 x;

    *got_a_frame = false;

    /* init the CRC */
    frame_crc = 0;
    frame_crc = FLAC__CRC16_UPDATE(decoder->private_->header_warmup[0], frame_crc);
    frame_crc = FLAC__CRC16_UPDATE(decoder->private_->header_warmup[1], frame_crc);
    FLAC__bitreader_reset_read_crc16(decoder->private_->input, (FLAC__uint16)frame_crc);

    if (!read_frame_header_(decoder))
        return false;
    if (decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC) /* means we didn't sync on a valid header */
        return true;
    if (!allocate_output_(decoder, decoder->private_->frame.header.blocksize, decoder->private_->frame.header.channels))
        return false;
    for (channel = 0; channel < decoder->private_->frame.header.channels; channel++)
    {
        /*
         * first figure the correct bits-per-sample of the subframe
         */
        unsigned bps = decoder->private_->frame.header.bits_per_sample;
        switch (decoder->private_->frame.header.channel_assignment)
        {
            case FLAC__CHANNEL_ASSIGNMENT_INDEPENDENT:
                /* no adjustment needed */
                break;
            case FLAC__CHANNEL_ASSIGNMENT_LEFT_SIDE:
                FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
                if (channel == 1)
                    bps++;
                break;
            case FLAC__CHANNEL_ASSIGNMENT_RIGHT_SIDE:
                FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
                if (channel == 0)
                    bps++;
                break;
            case FLAC__CHANNEL_ASSIGNMENT_MID_SIDE:
                FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
                if (channel == 1)
                    bps++;
                break;
            default:
                FLAC__ASSERT(0);
        }
        /*
         * now read it
         */
        if (!read_subframe_(decoder, channel, bps, do_full_decode))
            return false;
        if (decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC) /* means bad sync or got corruption */
            return true;
    }
    if (!read_zero_padding_(decoder))
        return false;
    if (decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC) /* means bad sync or got corruption (i.e. "zero bits" were not all zeroes) */
        return true;

    /*
     * Read the frame CRC-16 from the footer and check
     */
    frame_crc = FLAC__bitreader_get_read_crc16(decoder->private_->input);
    if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, FLAC__FRAME_FOOTER_CRC_LEN))
        return false; /* read_callback_ sets the state for us */
    if (frame_crc == x)
    {
        if (do_full_decode)
        {
            /* Undo any special channel coding */
            switch (decoder->private_->frame.header.channel_assignment)
            {
                case FLAC__CHANNEL_ASSIGNMENT_INDEPENDENT:
                    /* do nothing */
                    break;
                case FLAC__CHANNEL_ASSIGNMENT_LEFT_SIDE:
                    FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
                    for (i = 0; i < decoder->private_->frame.header.blocksize; i++)
                        decoder->private_->output[1][i] = decoder->private_->output[0][i] - decoder->private_->output[1][i];
                    break;
                case FLAC__CHANNEL_ASSIGNMENT_RIGHT_SIDE:
                    FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
                    for (i = 0; i < decoder->private_->frame.header.blocksize; i++)
                        decoder->private_->output[0][i] += decoder->private_->output[1][i];
                    break;
                case FLAC__CHANNEL_ASSIGNMENT_MID_SIDE:
                    FLAC__ASSERT(decoder->private_->frame.header.channels == 2);
                    for (i = 0; i < decoder->private_->frame.header.blocksize; i++)
                    {
                        #if 1
                        mid = decoder->private_->output[0][i];
                        side = decoder->private_->output[1][i];
                        mid <<= 1;
                        mid |= (side & 1); /* i.e. if 'side' is odd... */
                        decoder->private_->output[0][i] = (mid + side) >> 1;
                        decoder->private_->output[1][i] = (mid - side) >> 1;
                        #else
                        /* OPT: without 'side' temp variable */
                        mid = (decoder->private_->output[0][i] << 1) | (decoder->private_->output[1][i] & 1); /* i.e. if 'side' is odd... */
                        decoder->private_->output[0][i] = (mid + decoder->private_->output[1][i]) >> 1;
                        decoder->private_->output[1][i] = (mid - decoder->private_->output[1][i]) >> 1;
                        #endif
                    }
                    break;
                default:
                    FLAC__ASSERT(0);
                    break;
            }
        }
    }
    else
    {
        /* Bad frame, emit error and zero the output signal */
        send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_FRAME_CRC_MISMATCH);
        if (do_full_decode)
        {
            for (channel = 0; channel < decoder->private_->frame.header.channels; channel++)
            {
                memset(decoder->private_->output[channel], 0, sizeof(FLAC__int32) * decoder->private_->frame.header.blocksize);
            }
        }
    }

    *got_a_frame = true;

    /* we wait to update fixed_block_size until here, when we're sure we've got a proper frame and hence a correct blocksize */
    if (decoder->private_->next_fixed_block_size)
        decoder->private_->fixed_block_size = decoder->private_->next_fixed_block_size;

    /* put the latest values into the public section of the decoder instance */
    decoder->protected_->channels = decoder->private_->frame.header.channels;
    decoder->protected_->channel_assignment = decoder->private_->frame.header.channel_assignment;
    decoder->protected_->bits_per_sample = decoder->private_->frame.header.bits_per_sample;
    decoder->protected_->sample_rate = decoder->private_->frame.header.sample_rate;
    decoder->protected_->blocksize = decoder->private_->frame.header.blocksize;

    FLAC__ASSERT(decoder->private_->frame.header.number_type == FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER);
    decoder->private_->samples_decoded = decoder->private_->frame.header.number.sample_number + decoder->private_->frame.header.blocksize;

    /* write it */
    if (do_full_decode)
    {
        if (write_audio_frame_to_client_(decoder, &decoder->private_->frame, (const FLAC__int32* const*)decoder->private_->output) != FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE)
            return false;
    }

    decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
    return true;
}

FLAC__bool read_frame_header_(FLAC__StreamDecoder* decoder)
{
    FLAC__uint32 x;
    FLAC__uint64 xx;
    unsigned i, blocksize_hint = 0, sample_rate_hint = 0;
    FLAC__byte crc8, raw_header[16]; /* MAGIC NUMBER based on the maximum frame header size, including CRC */
    unsigned raw_header_len;
    FLAC__bool is_unparseable = false;

    FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input));

    /* init the raw header with the saved bits from synchronization */
    raw_header[0] = decoder->private_->header_warmup[0];
    raw_header[1] = decoder->private_->header_warmup[1];
    raw_header_len = 2;

    /* check to make sure that reserved bit is 0 */
    if (raw_header[1] & 0x02) /* MAGIC NUMBER */
        is_unparseable = true;

    /*
     * Note that along the way as we read the header, we look for a sync
     * code inside.  If we find one it would indicate that our original
     * sync was bad since there cannot be a sync code in a valid header.
     *
     * Three kinds of things can go wrong when reading the frame header:
     *  1) We may have sync'ed incorrectly and not landed on a frame header.
     *     If we don't find a sync code, it can end up looking like we read
     *     a valid but unparseable header, until getting to the frame header
     *     CRC.  Even then we could get a false positive on the CRC.
     *  2) We may have sync'ed correctly but on an unparseable frame (from a
     *     future encoder).
     *  3) We may be on a damaged frame which appears valid but unparseable.
     *
     * For all these reasons, we try and read a complete frame header as
     * long as it seems valid, even if unparseable, up until the frame
     * header CRC.
     */

    /*
     * read in the raw header as bytes so we can CRC it, and parse it on the way
     */
    for (i = 0; i < 2; i++)
    {
        if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
            return false; /* read_callback_ sets the state for us */
        if (x == 0xff)   /* MAGIC NUMBER for the first 8 frame sync bits */
        {   /* if we get here it means our original sync was erroneous since the sync code cannot appear in the header */
            decoder->private_->lookahead = (FLAC__byte)x;
            decoder->private_->cached = true;
            send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
            decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
            return true;
        }
        raw_header[raw_header_len++] = (FLAC__byte)x;
    }

    switch (x = raw_header[2] >> 4)
    {
        case 0:
            is_unparseable = true;
            break;
        case 1:
            decoder->private_->frame.header.blocksize = 192;
            break;
        case 2:
        case 3:
        case 4:
        case 5:
            decoder->private_->frame.header.blocksize = 576 << (x - 2);
            break;
        case 6:
        case 7:
            blocksize_hint = x;
            break;
        case 8:
        case 9:
        case 10:
        case 11:
        case 12:
        case 13:
        case 14:
        case 15:
            decoder->private_->frame.header.blocksize = 256 << (x - 8);
            break;
        default:
            FLAC__ASSERT(0);
            break;
    }

    switch (x = raw_header[2] & 0x0f)
    {
        case 0:
            if (decoder->private_->has_stream_info)
                decoder->private_->frame.header.sample_rate = decoder->private_->stream_info.data.stream_info.sample_rate;
            else
                is_unparseable = true;
            break;
        case 1:
            decoder->private_->frame.header.sample_rate = 88200;
            break;
        case 2:
            decoder->private_->frame.header.sample_rate = 176400;
            break;
        case 3:
            decoder->private_->frame.header.sample_rate = 192000;
            break;
        case 4:
            decoder->private_->frame.header.sample_rate = 8000;
            break;
        case 5:
            decoder->private_->frame.header.sample_rate = 16000;
            break;
        case 6:
            decoder->private_->frame.header.sample_rate = 22050;
            break;
        case 7:
            decoder->private_->frame.header.sample_rate = 24000;
            break;
        case 8:
            decoder->private_->frame.header.sample_rate = 32000;
            break;
        case 9:
            decoder->private_->frame.header.sample_rate = 44100;
            break;
        case 10:
            decoder->private_->frame.header.sample_rate = 48000;
            break;
        case 11:
            decoder->private_->frame.header.sample_rate = 96000;
            break;
        case 12:
        case 13:
        case 14:
            sample_rate_hint = x;
            break;
        case 15:
            send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
            decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
            return true;
        default:
            FLAC__ASSERT(0);
    }

    x = (unsigned)(raw_header[3] >> 4);
    if (x & 8)
    {
        decoder->private_->frame.header.channels = 2;
        switch (x & 7)
        {
            case 0:
                decoder->private_->frame.header.channel_assignment = FLAC__CHANNEL_ASSIGNMENT_LEFT_SIDE;
                break;
            case 1:
                decoder->private_->frame.header.channel_assignment = FLAC__CHANNEL_ASSIGNMENT_RIGHT_SIDE;
                break;
            case 2:
                decoder->private_->frame.header.channel_assignment = FLAC__CHANNEL_ASSIGNMENT_MID_SIDE;
                break;
            default:
                is_unparseable = true;
                break;
        }
    }
    else
    {
        decoder->private_->frame.header.channels = (unsigned)x + 1;
        decoder->private_->frame.header.channel_assignment = FLAC__CHANNEL_ASSIGNMENT_INDEPENDENT;
    }

    switch (x = (unsigned)(raw_header[3] & 0x0e) >> 1)
    {
        case 0:
            if (decoder->private_->has_stream_info)
                decoder->private_->frame.header.bits_per_sample = decoder->private_->stream_info.data.stream_info.bits_per_sample;
            else
                is_unparseable = true;
            break;
        case 1:
            decoder->private_->frame.header.bits_per_sample = 8;
            break;
        case 2:
            decoder->private_->frame.header.bits_per_sample = 12;
            break;
        case 4:
            decoder->private_->frame.header.bits_per_sample = 16;
            break;
        case 5:
            decoder->private_->frame.header.bits_per_sample = 20;
            break;
        case 6:
            decoder->private_->frame.header.bits_per_sample = 24;
            break;
        case 3:
        case 7:
            is_unparseable = true;
            break;
        default:
            FLAC__ASSERT(0);
            break;
    }

    /* check to make sure that reserved bit is 0 */
    if (raw_header[3] & 0x01) /* MAGIC NUMBER */
        is_unparseable = true;

    /* read the frame's starting sample number (or frame number as the case may be) */
    if (
        raw_header[1] & 0x01 ||
        /*@@@ this clause is a concession to the old way of doing variable blocksize; the only known implementation is flake and can probably be removed without inconveniencing anyone */
        (decoder->private_->has_stream_info && decoder->private_->stream_info.data.stream_info.min_blocksize != decoder->private_->stream_info.data.stream_info.max_blocksize)
        ) /* variable blocksize */
    {
        if (!FLAC__bitreader_read_utf8_uint64(decoder->private_->input, &xx, raw_header, &raw_header_len))
            return false; /* read_callback_ sets the state for us */
        if (xx == FLAC__U64L(0xffffffffffffffff))   /* i.e. non-UTF8 code... */
        {
            decoder->private_->lookahead = raw_header[raw_header_len - 1]; /* back up as much as we can */
            decoder->private_->cached = true;
            send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
            decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
            return true;
        }
        decoder->private_->frame.header.number_type = FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER;
        decoder->private_->frame.header.number.sample_number = xx;
    }
    else   /* fixed blocksize */
    {
        if (!FLAC__bitreader_read_utf8_uint32(decoder->private_->input, &x, raw_header, &raw_header_len))
            return false; /* read_callback_ sets the state for us */
        if (x == 0xffffffff)   /* i.e. non-UTF8 code... */
        {
            decoder->private_->lookahead = raw_header[raw_header_len - 1]; /* back up as much as we can */
            decoder->private_->cached = true;
            send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
            decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
            return true;
        }
        decoder->private_->frame.header.number_type = FLAC__FRAME_NUMBER_TYPE_FRAME_NUMBER;
        decoder->private_->frame.header.number.frame_number = x;
    }

    if (blocksize_hint)
    {
        if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
            return false; /* read_callback_ sets the state for us */
        raw_header[raw_header_len++] = (FLAC__byte)x;
        if (blocksize_hint == 7)
        {
            FLAC__uint32 _x;
            if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &_x, 8))
                return false; /* read_callback_ sets the state for us */
            raw_header[raw_header_len++] = (FLAC__byte)_x;
            x = (x << 8) | _x;
        }
        decoder->private_->frame.header.blocksize = x + 1;
    }

    if (sample_rate_hint)
    {
        if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
            return false; /* read_callback_ sets the state for us */
        raw_header[raw_header_len++] = (FLAC__byte)x;
        if (sample_rate_hint != 12)
        {
            FLAC__uint32 _x;
            if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &_x, 8))
                return false; /* read_callback_ sets the state for us */
            raw_header[raw_header_len++] = (FLAC__byte)_x;
            x = (x << 8) | _x;
        }
        if (sample_rate_hint == 12)
            decoder->private_->frame.header.sample_rate = x * 1000;
        else if (sample_rate_hint == 13)
            decoder->private_->frame.header.sample_rate = x;
        else
            decoder->private_->frame.header.sample_rate = x * 10;
    }

    /* read the CRC-8 byte */
    if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8))
        return false; /* read_callback_ sets the state for us */
    crc8 = (FLAC__byte)x;

    if (FLAC__crc8(raw_header, raw_header_len) != crc8)
    {
        send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_BAD_HEADER);
        decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
        return true;
    }

    /* calculate the sample number from the frame number if needed */
    decoder->private_->next_fixed_block_size = 0;
    if (decoder->private_->frame.header.number_type == FLAC__FRAME_NUMBER_TYPE_FRAME_NUMBER)
    {
        x = decoder->private_->frame.header.number.frame_number;
        decoder->private_->frame.header.number_type = FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER;
        if (decoder->private_->fixed_block_size)
            decoder->private_->frame.header.number.sample_number = (FLAC__uint64)decoder->private_->fixed_block_size * (FLAC__uint64)x;
        else if (decoder->private_->has_stream_info)
        {
            if (decoder->private_->stream_info.data.stream_info.min_blocksize == decoder->private_->stream_info.data.stream_info.max_blocksize)
            {
                decoder->private_->frame.header.number.sample_number = (FLAC__uint64)decoder->private_->stream_info.data.stream_info.min_blocksize * (FLAC__uint64)x;
                decoder->private_->next_fixed_block_size = decoder->private_->stream_info.data.stream_info.max_blocksize;
            }
            else
                is_unparseable = true;
        }
        else if (x == 0)
        {
            decoder->private_->frame.header.number.sample_number = 0;
            decoder->private_->next_fixed_block_size = decoder->private_->frame.header.blocksize;
        }
        else
        {
            /* can only get here if the stream has invalid frame numbering and no STREAMINFO, so assume it's not the last (possibly short) frame */
            decoder->private_->frame.header.number.sample_number = (FLAC__uint64)decoder->private_->frame.header.blocksize * (FLAC__uint64)x;
        }
    }

    if (is_unparseable)
    {
        send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
        decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
        return true;
    }

    return true;
}

FLAC__bool read_subframe_(FLAC__StreamDecoder* decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode)
{
    FLAC__uint32 x;
    FLAC__bool wasted_bits;
    unsigned i;

    if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &x, 8)) /* MAGIC NUMBER */
        return false; /* read_callback_ sets the state for us */

    wasted_bits = (x & 1);
    x &= 0xfe;

    if (wasted_bits)
    {
        unsigned u;
        if (!FLAC__bitreader_read_unary_unsigned(decoder->private_->input, &u))
            return false; /* read_callback_ sets the state for us */
        decoder->private_->frame.subframes[channel].wasted_bits = u + 1;
        bps -= decoder->private_->frame.subframes[channel].wasted_bits;
    }
    else
        decoder->private_->frame.subframes[channel].wasted_bits = 0;

    /*
     * Lots of magic numbers here
     */
    if (x & 0x80)
    {
        send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
        decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
        return true;
    }
    else if (x == 0)
    {
        if (!read_subframe_constant_(decoder, channel, bps, do_full_decode))
            return false;
    }
    else if (x == 2)
    {
        if (!read_subframe_verbatim_(decoder, channel, bps, do_full_decode))
            return false;
    }
    else if (x < 16)
    {
        send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
        decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
        return true;
    }
    else if (x <= 24)
    {
        if (!read_subframe_fixed_(decoder, channel, bps, (x >> 1) & 7, do_full_decode))
            return false;
        if (decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC) /* means bad sync or got corruption */
            return true;
    }
    else if (x < 64)
    {
        send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
        decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
        return true;
    }
    else
    {
        if (!read_subframe_lpc_(decoder, channel, bps, ((x >> 1) & 31) + 1, do_full_decode))
            return false;
        if (decoder->protected_->state == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC) /* means bad sync or got corruption */
            return true;
    }

    if (wasted_bits && do_full_decode)
    {
        x = decoder->private_->frame.subframes[channel].wasted_bits;
        for (i = 0; i < decoder->private_->frame.header.blocksize; i++)
            decoder->private_->output[channel][i] <<= x;
    }

    return true;
}

FLAC__bool read_subframe_constant_(FLAC__StreamDecoder* decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode)
{
    FLAC__Subframe_Constant* subframe = &decoder->private_->frame.subframes[channel].data.constant;
    FLAC__int32 x;
    unsigned i;
    FLAC__int32* output = decoder->private_->output[channel];

    decoder->private_->frame.subframes[channel].type = FLAC__SUBFRAME_TYPE_CONSTANT;

    if (!FLAC__bitreader_read_raw_int32(decoder->private_->input, &x, bps))
        return false; /* read_callback_ sets the state for us */

    subframe->value = x;

    /* decode the subframe */
    if (do_full_decode)
    {
        for (i = 0; i < decoder->private_->frame.header.blocksize; i++)
            output[i] = x;
    }

    return true;
}

FLAC__bool read_subframe_fixed_(FLAC__StreamDecoder* decoder, unsigned channel, unsigned bps, const unsigned order, FLAC__bool do_full_decode)
{
    FLAC__Subframe_Fixed* subframe = &decoder->private_->frame.subframes[channel].data.fixed;
    FLAC__int32 i32;
    FLAC__uint32 u32;
    unsigned u;

    decoder->private_->frame.subframes[channel].type = FLAC__SUBFRAME_TYPE_FIXED;

    subframe->residual = decoder->private_->residual[channel];
    subframe->order = order;

    /* read warm-up samples */
    for (u = 0; u < order; u++)
    {
        if (!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i32, bps))
            return false; /* read_callback_ sets the state for us */
        subframe->warmup[u] = i32;
    }

    /* read entropy coding method info */
    if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__ENTROPY_CODING_METHOD_TYPE_LEN))
        return false; /* read_callback_ sets the state for us */
    subframe->entropy_coding_method.type = (FLAC__EntropyCodingMethodType)u32;
    switch (subframe->entropy_coding_method.type)
    {
        case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE:
        case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2:
            if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ORDER_LEN))
                return false; /* read_callback_ sets the state for us */
            subframe->entropy_coding_method.data.partitioned_rice.order = u32;
            subframe->entropy_coding_method.data.partitioned_rice.contents = &decoder->private_->partitioned_rice_contents[channel];
            break;
        default:
            send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
            decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
            return true;
    }

    /* read residual */
    switch (subframe->entropy_coding_method.type)
    {
        case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE:
        case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2:
            if (!read_residual_partitioned_rice_(decoder, order, subframe->entropy_coding_method.data.partitioned_rice.order, &decoder->private_->partitioned_rice_contents[channel], decoder->private_->residual[channel], /*is_extended=*/ subframe->entropy_coding_method.type == FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2))
                return false;
            break;
        default:
            FLAC__ASSERT(0);
    }

    /* decode the subframe */
    if (do_full_decode)
    {
        memcpy(decoder->private_->output[channel], subframe->warmup, sizeof(FLAC__int32) * order);
        FLAC__fixed_restore_signal(decoder->private_->residual[channel], decoder->private_->frame.header.blocksize - order, order, decoder->private_->output[channel] + order);
    }

    return true;
}

FLAC__bool read_subframe_lpc_(FLAC__StreamDecoder* decoder, unsigned channel, unsigned bps, const unsigned order, FLAC__bool do_full_decode)
{
    FLAC__Subframe_LPC* subframe = &decoder->private_->frame.subframes[channel].data.lpc;
    FLAC__int32 i32;
    FLAC__uint32 u32;
    unsigned u;

    decoder->private_->frame.subframes[channel].type = FLAC__SUBFRAME_TYPE_LPC;

    subframe->residual = decoder->private_->residual[channel];
    subframe->order = order;

    /* read warm-up samples */
    for (u = 0; u < order; u++)
    {
        if (!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i32, bps))
            return false; /* read_callback_ sets the state for us */
        subframe->warmup[u] = i32;
    }

    /* read qlp coeff precision */
    if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__SUBFRAME_LPC_QLP_COEFF_PRECISION_LEN))
        return false; /* read_callback_ sets the state for us */
    if (u32 == (1u << FLAC__SUBFRAME_LPC_QLP_COEFF_PRECISION_LEN) - 1)
    {
        send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
        decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
        return true;
    }
    subframe->qlp_coeff_precision = u32 + 1;

    /* read qlp shift */
    if (!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i32, FLAC__SUBFRAME_LPC_QLP_SHIFT_LEN))
        return false; /* read_callback_ sets the state for us */
    subframe->quantization_level = i32;

    /* read quantized lp coefficiencts */
    for (u = 0; u < order; u++)
    {
        if (!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i32, subframe->qlp_coeff_precision))
            return false; /* read_callback_ sets the state for us */
        subframe->qlp_coeff[u] = i32;
    }

    /* read entropy coding method info */
    if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__ENTROPY_CODING_METHOD_TYPE_LEN))
        return false; /* read_callback_ sets the state for us */
    subframe->entropy_coding_method.type = (FLAC__EntropyCodingMethodType)u32;
    switch (subframe->entropy_coding_method.type)
    {
        case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE:
        case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2:
            if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &u32, FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ORDER_LEN))
                return false; /* read_callback_ sets the state for us */
            subframe->entropy_coding_method.data.partitioned_rice.order = u32;
            subframe->entropy_coding_method.data.partitioned_rice.contents = &decoder->private_->partitioned_rice_contents[channel];
            break;
        default:
            send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM);
            decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
            return true;
    }

    /* read residual */
    switch (subframe->entropy_coding_method.type)
    {
        case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE:
        case FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2:
            if (!read_residual_partitioned_rice_(decoder, order, subframe->entropy_coding_method.data.partitioned_rice.order, &decoder->private_->partitioned_rice_contents[channel], decoder->private_->residual[channel], /*is_extended=*/ subframe->entropy_coding_method.type == FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2))
                return false;
            break;
        default:
            FLAC__ASSERT(0);
    }

    /* decode the subframe */
    if (do_full_decode)
    {
        memcpy(decoder->private_->output[channel], subframe->warmup, sizeof(FLAC__int32) * order);
        /*@@@@@@ technically not pessimistic enough, should be more like
           if( (FLAC__uint64)order * ((((FLAC__uint64)1)<<bps)-1) * ((1<<subframe->qlp_coeff_precision)-1) < (((FLAC__uint64)-1) << 32) )
         */
        if (bps + subframe->qlp_coeff_precision + FLAC__bitmath_ilog2(order) <= 32)
            if (bps <= 16 && subframe->qlp_coeff_precision <= 16)
            {
                if (order <= 8)
                    decoder->private_->local_lpc_restore_signal_16bit_order8(decoder->private_->residual[channel], decoder->private_->frame.header.blocksize - order, subframe->qlp_coeff, order, subframe->quantization_level, decoder->private_->output[channel] + order);
                else
                    decoder->private_->local_lpc_restore_signal_16bit(decoder->private_->residual[channel], decoder->private_->frame.header.blocksize - order, subframe->qlp_coeff, order, subframe->quantization_level, decoder->private_->output[channel] + order);
            }
            else
                decoder->private_->local_lpc_restore_signal(decoder->private_->residual[channel], decoder->private_->frame.header.blocksize - order, subframe->qlp_coeff, order, subframe->quantization_level, decoder->private_->output[channel] + order);
        else
            decoder->private_->local_lpc_restore_signal_64bit(decoder->private_->residual[channel], decoder->private_->frame.header.blocksize - order, subframe->qlp_coeff, order, subframe->quantization_level, decoder->private_->output[channel] + order);
    }

    return true;
}

FLAC__bool read_subframe_verbatim_(FLAC__StreamDecoder* decoder, unsigned channel, unsigned bps, FLAC__bool do_full_decode)
{
    FLAC__Subframe_Verbatim* subframe = &decoder->private_->frame.subframes[channel].data.verbatim;
    FLAC__int32 x, * residual = decoder->private_->residual[channel];
    unsigned i;

    decoder->private_->frame.subframes[channel].type = FLAC__SUBFRAME_TYPE_VERBATIM;

    subframe->data = residual;

    for (i = 0; i < decoder->private_->frame.header.blocksize; i++)
    {
        if (!FLAC__bitreader_read_raw_int32(decoder->private_->input, &x, bps))
            return false; /* read_callback_ sets the state for us */
        residual[i] = x;
    }

    /* decode the subframe */
    if (do_full_decode)
        memcpy(decoder->private_->output[channel], subframe->data, sizeof(FLAC__int32) * decoder->private_->frame.header.blocksize);

    return true;
}

FLAC__bool read_residual_partitioned_rice_(FLAC__StreamDecoder* decoder, unsigned predictor_order, unsigned partition_order, FLAC__EntropyCodingMethod_PartitionedRiceContents* partitioned_rice_contents, FLAC__int32* residual, FLAC__bool is_extended)
{
    FLAC__uint32 rice_parameter;
    int i;
    unsigned partition, sample, u;
    const unsigned partitions = 1u << partition_order;
    const unsigned partition_samples = partition_order > 0 ? decoder->private_->frame.header.blocksize >> partition_order : decoder->private_->frame.header.blocksize - predictor_order;
    const unsigned plen = is_extended ? FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2_PARAMETER_LEN : FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_PARAMETER_LEN;
    const unsigned pesc = is_extended ? FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE2_ESCAPE_PARAMETER : FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ESCAPE_PARAMETER;

    /* sanity checks */
    if (partition_order == 0)
    {
        if (decoder->private_->frame.header.blocksize < predictor_order)
        {
            send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
            decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
            return true;
        }
    }
    else
    {
        if (partition_samples < predictor_order)
        {
            send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
            decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
            return true;
        }
    }

    if (!FLAC__format_entropy_coding_method_partitioned_rice_contents_ensure_size(partitioned_rice_contents, max(6, partition_order)))
    {
        decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
        return false;
    }

    sample = 0;
    for (partition = 0; partition < partitions; partition++)
    {
        if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &rice_parameter, plen))
            return false; /* read_callback_ sets the state for us */
        partitioned_rice_contents->parameters[partition] = rice_parameter;
        if (rice_parameter < pesc)
        {
            partitioned_rice_contents->raw_bits[partition] = 0;
            u = (partition_order == 0 || partition > 0) ? partition_samples : partition_samples - predictor_order;
            if (!decoder->private_->local_bitreader_read_rice_signed_block(decoder->private_->input, residual + sample, u, rice_parameter))
                return false; /* read_callback_ sets the state for us */
            sample += u;
        }
        else
        {
            if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &rice_parameter, FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_RAW_LEN))
                return false; /* read_callback_ sets the state for us */
            partitioned_rice_contents->raw_bits[partition] = rice_parameter;
            for (u = (partition_order == 0 || partition > 0) ? 0 : predictor_order; u < partition_samples; u++, sample++)
            {
                if (!FLAC__bitreader_read_raw_int32(decoder->private_->input, &i, rice_parameter))
                    return false; /* read_callback_ sets the state for us */
                residual[sample] = i;
            }
        }
    }

    return true;
}

FLAC__bool read_zero_padding_(FLAC__StreamDecoder* decoder)
{
    if (!FLAC__bitreader_is_consumed_byte_aligned(decoder->private_->input))
    {
        FLAC__uint32 zero = 0;
        if (!FLAC__bitreader_read_raw_uint32(decoder->private_->input, &zero, FLAC__bitreader_bits_left_for_byte_alignment(decoder->private_->input)))
            return false; /* read_callback_ sets the state for us */
        if (zero != 0)
        {
            send_error_to_client_(decoder, FLAC__STREAM_DECODER_ERROR_STATUS_LOST_SYNC);
            decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;
        }
    }
    return true;
}

FLAC__bool read_callback_(FLAC__byte buffer[], size_t* bytes, void* client_data)
{
    FLAC__StreamDecoder* decoder = (FLAC__StreamDecoder*)client_data;

    if (
        #if FLAC__HAS_OGG
        /* see [1] HACK NOTE below for why we don't call the eof_callback when decoding Ogg FLAC */
        !decoder->private_->is_ogg &&
        #endif
        decoder->private_->eof_callback && decoder->private_->eof_callback(decoder, decoder->private_->client_data)
        )
    {
        *bytes = 0;
        decoder->protected_->state = FLAC__STREAM_DECODER_END_OF_STREAM;
        return false;
    }
    else if (*bytes > 0)
    {
        /* While seeking, it is possible for our seek to land in the
         * middle of audio data that looks exactly like a frame header
         * from a future version of an encoder.  When that happens, our
         * error callback will get an
         * FLAC__STREAM_DECODER_UNPARSEABLE_STREAM and increment its
         * unparseable_frame_count.  But there is a remote possibility
         * that it is properly synced at such a "future-codec frame",
         * so to make sure, we wait to see many "unparseable" errors in
         * a row before bailing out.
         */
        if (decoder->private_->is_seeking && decoder->private_->unparseable_frame_count > 20)
        {
            decoder->protected_->state = FLAC__STREAM_DECODER_ABORTED;
            return false;
        }
        else
        {
            const FLAC__StreamDecoderReadStatus status =
                #if FLAC__HAS_OGG
                decoder->private_->is_ogg ?
                read_callback_ogg_aspect_(decoder, buffer, bytes) :
                #endif
                decoder->private_->read_callback(decoder, buffer, bytes, decoder->private_->client_data)
            ;
            if (status == FLAC__STREAM_DECODER_READ_STATUS_ABORT)
            {
                decoder->protected_->state = FLAC__STREAM_DECODER_ABORTED;
                return false;
            }
            else if (*bytes == 0)
            {
                if (
                    status == FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM ||
                    (
                        #if FLAC__HAS_OGG
                        /* see [1] HACK NOTE below for why we don't call the eof_callback when decoding Ogg FLAC */
                        !decoder->private_->is_ogg &&
                        #endif
                        decoder->private_->eof_callback && decoder->private_->eof_callback(decoder, decoder->private_->client_data)
                    )
                    )
                {
                    decoder->protected_->state = FLAC__STREAM_DECODER_END_OF_STREAM;
                    return false;
                }
                else
                    return true;
            }
            else
                return true;
        }
    }
    else
    {
        /* abort to avoid a deadlock */
        decoder->protected_->state = FLAC__STREAM_DECODER_ABORTED;
        return false;
    }
    /* [1] @@@ HACK NOTE: The end-of-stream checking has to be hacked around
     * for Ogg FLAC.  This is because the ogg decoder aspect can lose sync
     * and at the same time hit the end of the stream (for example, seeking
     * to a point that is after the beginning of the last Ogg page).  There
     * is no way to report an Ogg sync loss through the callbacks (see note
     * in read_callback_ogg_aspect_()) so it returns CONTINUE with *bytes==0.
     * So to keep the decoder from stopping at this point we gate the call
     * to the eof_callback and let the Ogg decoder aspect set the
     * end-of-stream state when it is needed.
     */
}

#if FLAC__HAS_OGG
FLAC__StreamDecoderReadStatus read_callback_ogg_aspect_(const FLAC__StreamDecoder* decoder, FLAC__byte buffer[], size_t* bytes)
{
    switch (FLAC__ogg_decoder_aspect_read_callback_wrapper(&decoder->protected_->ogg_decoder_aspect, buffer, bytes, read_callback_proxy_, decoder, decoder->private_->client_data))
    {
        case FLAC__OGG_DECODER_ASPECT_READ_STATUS_OK:
            return FLAC__STREAM_DECODER_READ_STATUS_CONTINUE;
        /* we don't really have a way to handle lost sync via read
         * callback so we'll let it pass and let the underlying
         * FLAC decoder catch the error
         */
        case FLAC__OGG_DECODER_ASPECT_READ_STATUS_LOST_SYNC:
            return FLAC__STREAM_DECODER_READ_STATUS_CONTINUE;
        case FLAC__OGG_DECODER_ASPECT_READ_STATUS_END_OF_STREAM:
            return FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM;
        case FLAC__OGG_DECODER_ASPECT_READ_STATUS_NOT_FLAC:
        case FLAC__OGG_DECODER_ASPECT_READ_STATUS_UNSUPPORTED_MAPPING_VERSION:
        case FLAC__OGG_DECODER_ASPECT_READ_STATUS_ABORT:
        case FLAC__OGG_DECODER_ASPECT_READ_STATUS_ERROR:
        case FLAC__OGG_DECODER_ASPECT_READ_STATUS_MEMORY_ALLOCATION_ERROR:
            return FLAC__STREAM_DECODER_READ_STATUS_ABORT;
        default:
            FLAC__ASSERT(0);
            /* double protection */
            return FLAC__STREAM_DECODER_READ_STATUS_ABORT;
    }
}

FLAC__OggDecoderAspectReadStatus read_callback_proxy_(const void* void_decoder, FLAC__byte buffer[], size_t* bytes, void* client_data)
{
    FLAC__StreamDecoder* decoder = (FLAC__StreamDecoder*)void_decoder;

    switch (decoder->private_->read_callback(decoder, buffer, bytes, client_data))
    {
        case FLAC__STREAM_DECODER_READ_STATUS_CONTINUE:
            return FLAC__OGG_DECODER_ASPECT_READ_STATUS_OK;
        case FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM:
            return FLAC__OGG_DECODER_ASPECT_READ_STATUS_END_OF_STREAM;
        case FLAC__STREAM_DECODER_READ_STATUS_ABORT:
            return FLAC__OGG_DECODER_ASPECT_READ_STATUS_ABORT;
        default:
            /* double protection: */
            FLAC__ASSERT(0);
            return FLAC__OGG_DECODER_ASPECT_READ_STATUS_ABORT;
    }
}
#endif

FLAC__StreamDecoderWriteStatus write_audio_frame_to_client_(FLAC__StreamDecoder* decoder, const FLAC__Frame* frame, const FLAC__int32* const buffer[])
{
    if (decoder->private_->is_seeking)
    {
        FLAC__uint64 this_frame_sample = frame->header.number.sample_number;
        FLAC__uint64 next_frame_sample = this_frame_sample + (FLAC__uint64)frame->header.blocksize;
        FLAC__uint64 target_sample = decoder->private_->target_sample;

        FLAC__ASSERT(frame->header.number_type == FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER);

        #if FLAC__HAS_OGG
        decoder->private_->got_a_frame = true;
        #endif
        decoder->private_->last_frame = *frame; /* save the frame */
        if (this_frame_sample <= target_sample && target_sample < next_frame_sample)   /* we hit our target frame */
        {
            unsigned delta = (unsigned)(target_sample - this_frame_sample);
            /* kick out of seek mode */
            decoder->private_->is_seeking = false;
            /* shift out the samples before target_sample */
            if (delta > 0)
            {
                unsigned channel;
                const FLAC__int32* newbuffer[FLAC__MAX_CHANNELS];
                for (channel = 0; channel < frame->header.channels; channel++)
                    newbuffer[channel] = buffer[channel] + delta;
                decoder->private_->last_frame.header.blocksize -= delta;
                decoder->private_->last_frame.header.number.sample_number += (FLAC__uint64)delta;
                /* write the relevant samples */
                return decoder->private_->write_callback(decoder, &decoder->private_->last_frame, newbuffer, decoder->private_->client_data);
            }
            else
            {
                /* write the relevant samples */
                return decoder->private_->write_callback(decoder, frame, buffer, decoder->private_->client_data);
            }
        }
        else
        {
            return FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE;
        }
    }
    else
    {
        /*
         * If we never got STREAMINFO, turn off MD5 checking to save
         * cycles since we don't have a sum to compare to anyway
         */
        if (!decoder->private_->has_stream_info)
            decoder->private_->do_md5_checking = false;
        if (decoder->private_->do_md5_checking)
        {
            if (!FLAC__MD5Accumulate(&decoder->private_->md5context, buffer, frame->header.channels, frame->header.blocksize, (frame->header.bits_per_sample + 7) / 8))
                return FLAC__STREAM_DECODER_WRITE_STATUS_ABORT;
        }
        return decoder->private_->write_callback(decoder, frame, buffer, decoder->private_->client_data);
    }
}

void send_error_to_client_(const FLAC__StreamDecoder* decoder, FLAC__StreamDecoderErrorStatus status)
{
    if (!decoder->private_->is_seeking)
        decoder->private_->error_callback(decoder, status, decoder->private_->client_data);
    else if (status == FLAC__STREAM_DECODER_ERROR_STATUS_UNPARSEABLE_STREAM)
        decoder->private_->unparseable_frame_count++;
}

FLAC__bool seek_to_absolute_sample_(FLAC__StreamDecoder* decoder, FLAC__uint64 stream_length, FLAC__uint64 target_sample)
{
    FLAC__uint64 first_frame_offset = decoder->private_->first_frame_offset, lower_bound, upper_bound, lower_bound_sample, upper_bound_sample, this_frame_sample;
    FLAC__int64 pos = -1;
    int i;
    unsigned approx_bytes_per_frame;
    FLAC__bool first_seek = true;
    const FLAC__uint64 total_samples = FLAC__stream_decoder_get_total_samples(decoder);
    const unsigned min_blocksize = decoder->private_->stream_info.data.stream_info.min_blocksize;
    const unsigned max_blocksize = decoder->private_->stream_info.data.stream_info.max_blocksize;
    const unsigned max_framesize = decoder->private_->stream_info.data.stream_info.max_framesize;
    const unsigned min_framesize = decoder->private_->stream_info.data.stream_info.min_framesize;
    /* take these from the current frame in case they've changed mid-stream */
    unsigned channels = FLAC__stream_decoder_get_channels(decoder);
    unsigned bps = FLAC__stream_decoder_get_bits_per_sample(decoder);
    const FLAC__StreamMetadata_SeekTable* seek_table = decoder->private_->has_seek_table ? &decoder->private_->seek_table.data.seek_table : 0;

    /* use values from stream info if we didn't decode a frame */
    if (channels == 0)
        channels = decoder->private_->stream_info.data.stream_info.channels;
    if (bps == 0)
        bps = decoder->private_->stream_info.data.stream_info.bits_per_sample;

    /* we are just guessing here */
    if (max_framesize > 0)
        approx_bytes_per_frame = (max_framesize + min_framesize) / 2 + 1;
    /*
     * Check if it's a known fixed-blocksize stream.  Note that though
     * the spec doesn't allow zeroes in the STREAMINFO block, we may
     * never get a STREAMINFO block when decoding so the value of
     * min_blocksize might be zero.
     */
    else if (min_blocksize == max_blocksize && min_blocksize > 0)
    {
        /* note there are no () around 'bps/8' to keep precision up since it's an integer calulation */
        approx_bytes_per_frame = min_blocksize * channels * bps / 8 + 64;
    }
    else
        approx_bytes_per_frame = 4096 * channels * bps / 8 + 64;

    /*
     * First, we set an upper and lower bound on where in the
     * stream we will search.  For now we assume the worst case
     * scenario, which is our best guess at the beginning of
     * the first frame and end of the stream.
     */
    lower_bound = first_frame_offset;
    lower_bound_sample = 0;
    upper_bound = stream_length;
    upper_bound_sample = total_samples > 0 ? total_samples : target_sample /*estimate it*/;

    /*
     * Now we refine the bounds if we have a seektable with
     * suitable points.  Note that according to the spec they
     * must be ordered by ascending sample number.
     *
     * Note: to protect against invalid seek tables we will ignore points
     * that have frame_samples==0 or sample_number>=total_samples
     */
    if (seek_table)
    {
        FLAC__uint64 new_lower_bound = lower_bound;
        FLAC__uint64 new_upper_bound = upper_bound;
        FLAC__uint64 new_lower_bound_sample = lower_bound_sample;
        FLAC__uint64 new_upper_bound_sample = upper_bound_sample;

        /* find the closest seek point <= target_sample, if it exists */
        for (i = (int)seek_table->num_points - 1; i >= 0; i--)
        {
            if (
                seek_table->points[i].sample_number != FLAC__STREAM_METADATA_SEEKPOINT_PLACEHOLDER &&
                seek_table->points[i].frame_samples > 0 && /* defense against bad seekpoints */
                (total_samples <= 0 || seek_table->points[i].sample_number < total_samples) && /* defense against bad seekpoints */
                seek_table->points[i].sample_number <= target_sample
                )
                break;
        }
        if (i >= 0)   /* i.e. we found a suitable seek point... */
        {
            new_lower_bound = first_frame_offset + seek_table->points[i].stream_offset;
            new_lower_bound_sample = seek_table->points[i].sample_number;
        }

        /* find the closest seek point > target_sample, if it exists */
        for (i = 0; i < (int)seek_table->num_points; i++)
        {
            if (
                seek_table->points[i].sample_number != FLAC__STREAM_METADATA_SEEKPOINT_PLACEHOLDER &&
                seek_table->points[i].frame_samples > 0 && /* defense against bad seekpoints */
                (total_samples <= 0 || seek_table->points[i].sample_number < total_samples) && /* defense against bad seekpoints */
                seek_table->points[i].sample_number > target_sample
                )
                break;
        }
        if (i < (int)seek_table->num_points)   /* i.e. we found a suitable seek point... */
        {
            new_upper_bound = first_frame_offset + seek_table->points[i].stream_offset;
            new_upper_bound_sample = seek_table->points[i].sample_number;
        }
        /* final protection against unsorted seek tables; keep original values if bogus */
        if (new_upper_bound >= new_lower_bound)
        {
            lower_bound = new_lower_bound;
            upper_bound = new_upper_bound;
            lower_bound_sample = new_lower_bound_sample;
            upper_bound_sample = new_upper_bound_sample;
        }
    }

    FLAC__ASSERT(upper_bound_sample >= lower_bound_sample);
    /* there are 2 insidious ways that the following equality occurs, which
     * we need to fix:
     *  1) total_samples is 0 (unknown) and target_sample is 0
     *  2) total_samples is 0 (unknown) and target_sample happens to be
     *     exactly equal to the last seek point in the seek table; this
     *     means there is no seek point above it, and upper_bound_samples
     *     remains equal to the estimate (of target_samples) we made above
     * in either case it does not hurt to move upper_bound_sample up by 1
     */
    if (upper_bound_sample == lower_bound_sample)
        upper_bound_sample++;

    decoder->private_->target_sample = target_sample;
    while (1)
    {
        /* check if the bounds are still ok */
        if (lower_bound_sample >= upper_bound_sample || lower_bound > upper_bound)
        {
            decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
            return false;
        }
        #ifndef FLAC__INTEGER_ONLY_LIBRARY
        #if defined _MSC_VER || defined __MINGW32__
        /* with VC++ you have to spoon feed it the casting */
        pos = (FLAC__int64)lower_bound + (FLAC__int64)((FLAC__double)(FLAC__int64)(target_sample - lower_bound_sample) / (FLAC__double)(FLAC__int64)(upper_bound_sample - lower_bound_sample) * (FLAC__double)(FLAC__int64)(upper_bound - lower_bound)) - approx_bytes_per_frame;
        #else
        pos = (FLAC__int64)lower_bound + (FLAC__int64)((FLAC__double)(target_sample - lower_bound_sample) / (FLAC__double)(upper_bound_sample - lower_bound_sample) * (FLAC__double)(upper_bound - lower_bound)) - approx_bytes_per_frame;
        #endif
        #else
        /* a little less accurate: */
        if (upper_bound - lower_bound < 0xffffffff)
            pos = (FLAC__int64)lower_bound + (FLAC__int64)(((target_sample - lower_bound_sample) * (upper_bound - lower_bound)) / (upper_bound_sample - lower_bound_sample)) - approx_bytes_per_frame;
        else /* @@@ WATCHOUT, ~2TB limit */
            pos = (FLAC__int64)lower_bound + (FLAC__int64)((((target_sample - lower_bound_sample) >> 8) * ((upper_bound - lower_bound) >> 8)) / ((upper_bound_sample - lower_bound_sample) >> 16)) - approx_bytes_per_frame;
        #endif
        if (pos >= (FLAC__int64)upper_bound)
            pos = (FLAC__int64)upper_bound - 1;
        if (pos < (FLAC__int64)lower_bound)
            pos = (FLAC__int64)lower_bound;
        if (decoder->private_->seek_callback(decoder, (FLAC__uint64)pos, decoder->private_->client_data) != FLAC__STREAM_DECODER_SEEK_STATUS_OK)
        {
            decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
            return false;
        }
        if (!FLAC__stream_decoder_flush(decoder))
        {
            /* above call sets the state for us */
            return false;
        }
        /* Now we need to get a frame.  First we need to reset our
         * unparseable_frame_count; if we get too many unparseable
         * frames in a row, the read callback will return
         * FLAC__STREAM_DECODER_READ_STATUS_ABORT, causing
         * FLAC__stream_decoder_process_single() to return false.
         */
        decoder->private_->unparseable_frame_count = 0;
        if (!FLAC__stream_decoder_process_single(decoder))
        {
            decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
            return false;
        }
        /* our write callback will change the state when it gets to the target frame */
        /* actually, we could have got_a_frame if our decoder is at FLAC__STREAM_DECODER_END_OF_STREAM so we need to check for that also */
        #if 0
        /*@@@@@@ used to be the following; not clear if the check for end of stream is needed anymore */
        if (decoder->protected_->state != FLAC__SEEKABLE_STREAM_DECODER_SEEKING && decoder->protected_->state != FLAC__STREAM_DECODER_END_OF_STREAM)
            break;
        #endif
        if (!decoder->private_->is_seeking)
            break;

        FLAC__ASSERT(decoder->private_->last_frame.header.number_type == FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER);
        this_frame_sample = decoder->private_->last_frame.header.number.sample_number;

        if (0 == decoder->private_->samples_decoded || (this_frame_sample + decoder->private_->last_frame.header.blocksize >= upper_bound_sample && !first_seek))
        {
            if (pos == (FLAC__int64)lower_bound)
            {
                /* can't move back any more than the first frame, something is fatally wrong */
                decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
                return false;
            }
            /* our last move backwards wasn't big enough, try again */
            approx_bytes_per_frame = approx_bytes_per_frame ? approx_bytes_per_frame * 2 : 16;
            continue;
        }
        /* allow one seek over upper bound, so we can get a correct upper_bound_sample for streams with unknown total_samples */
        first_seek = false;

        /* make sure we are not seeking in corrupted stream */
        if (this_frame_sample < lower_bound_sample)
        {
            decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
            return false;
        }

        /* we need to narrow the search */
        if (target_sample < this_frame_sample)
        {
            upper_bound_sample = this_frame_sample + decoder->private_->last_frame.header.blocksize;
            /*@@@@@@ what will decode position be if at end of stream? */
            if (!FLAC__stream_decoder_get_decode_position(decoder, &upper_bound))
            {
                decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
                return false;
            }
            approx_bytes_per_frame = (unsigned)(2 * (upper_bound - pos) / 3 + 16);
        }
        else   /* target_sample >= this_frame_sample + this frame's blocksize */
        {
            lower_bound_sample = this_frame_sample + decoder->private_->last_frame.header.blocksize;
            if (!FLAC__stream_decoder_get_decode_position(decoder, &lower_bound))
            {
                decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
                return false;
            }
            approx_bytes_per_frame = (unsigned)(2 * (lower_bound - pos) / 3 + 16);
        }
    }

    return true;
}

#if FLAC__HAS_OGG
FLAC__bool seek_to_absolute_sample_ogg_(FLAC__StreamDecoder* decoder, FLAC__uint64 stream_length, FLAC__uint64 target_sample)
{
    FLAC__uint64 left_pos = 0, right_pos = stream_length;
    FLAC__uint64 left_sample = 0, right_sample = FLAC__stream_decoder_get_total_samples(decoder);
    FLAC__uint64 this_frame_sample = (FLAC__uint64)0 - 1;
    FLAC__uint64 pos = 0; /* only initialized to avoid compiler warning */
    FLAC__bool did_a_seek;
    unsigned iteration = 0;

    /* In the first iterations, we will calculate the target byte position
     * by the distance from the target sample to left_sample and
     * right_sample (let's call it "proportional search").  After that, we
     * will switch to binary search.
     */
    unsigned BINARY_SEARCH_AFTER_ITERATION = 2;

    /* We will switch to a linear search once our current sample is less
     * than this number of samples ahead of the target sample
     */
    static const FLAC__uint64 LINEAR_SEARCH_WITHIN_SAMPLES = FLAC__MAX_BLOCK_SIZE * 2;

    /* If the total number of samples is unknown, use a large value, and
     * force binary search immediately.
     */
    if (right_sample == 0)
    {
        right_sample = (FLAC__uint64)(-1);
        BINARY_SEARCH_AFTER_ITERATION = 0;
    }

    decoder->private_->target_sample = target_sample;
    for (;; iteration++)
    {
        if (iteration == 0 || this_frame_sample > target_sample || target_sample - this_frame_sample > LINEAR_SEARCH_WITHIN_SAMPLES)
        {
            if (iteration >= BINARY_SEARCH_AFTER_ITERATION)
            {
                pos = (right_pos + left_pos) / 2;
            }
            else
            {
                #ifndef FLAC__INTEGER_ONLY_LIBRARY
                #if defined _MSC_VER || defined __MINGW32__
                /* with MSVC you have to spoon feed it the casting */
                pos = (FLAC__uint64)((FLAC__double)(FLAC__int64)(target_sample - left_sample) / (FLAC__double)(FLAC__int64)(right_sample - left_sample) * (FLAC__double)(FLAC__int64)(right_pos - left_pos));
                #else
                pos = (FLAC__uint64)((FLAC__double)(target_sample - left_sample) / (FLAC__double)(right_sample - left_sample) * (FLAC__double)(right_pos - left_pos));
                #endif
                #else
                /* a little less accurate: */
                if ((target_sample - left_sample <= 0xffffffff) && (right_pos - left_pos <= 0xffffffff))
                    pos = (FLAC__int64)(((target_sample - left_sample) * (right_pos - left_pos)) / (right_sample - left_sample));
                else /* @@@ WATCHOUT, ~2TB limit */
                    pos = (FLAC__int64)((((target_sample - left_sample) >> 8) * ((right_pos - left_pos) >> 8)) / ((right_sample - left_sample) >> 16));
                #endif
                /* @@@ TODOx: might want to limit pos to some distance
                 * before EOF, to make sure we land before the last frame,
                 * thereby getting a this_frame_sample and so having a better
                 * estimate.
                 */
            }

            /* physical seek */
            if (decoder->private_->seek_callback((FLAC__StreamDecoder*)decoder, (FLAC__uint64)pos, decoder->private_->client_data) != FLAC__STREAM_DECODER_SEEK_STATUS_OK)
            {
                decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
                return false;
            }
            if (!FLAC__stream_decoder_flush(decoder))
            {
                /* above call sets the state for us */
                return false;
            }
            did_a_seek = true;
        }
        else
            did_a_seek = false;

        decoder->private_->got_a_frame = false;
        if (!FLAC__stream_decoder_process_single(decoder))
        {
            decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
            return false;
        }
        if (!decoder->private_->got_a_frame)
        {
            if (did_a_seek)
            {
                /* this can happen if we seek to a point after the last frame; we drop
                 * to binary search right away in this case to avoid any wasted
                 * iterations of proportional search.
                 */
                right_pos = pos;
                BINARY_SEARCH_AFTER_ITERATION = 0;
            }
            else
            {
                /* this can probably only happen if total_samples is unknown and the
                 * target_sample is past the end of the stream
                 */
                decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
                return false;
            }
        }
        /* our write callback will change the state when it gets to the target frame */
        else if (!decoder->private_->is_seeking)
        {
            break;
        }
        else
        {
            this_frame_sample = decoder->private_->last_frame.header.number.sample_number;
            FLAC__ASSERT(decoder->private_->last_frame.header.number_type == FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER);

            if (did_a_seek)
            {
                if (this_frame_sample <= target_sample)
                {
                    /* The 'equal' case should not happen, since
                     * FLAC__stream_decoder_process_single()
                     * should recognize that it has hit the
                     * target sample and we would exit through
                     * the 'break' above.
                     */
                    FLAC__ASSERT(this_frame_sample != target_sample);

                    left_sample = this_frame_sample;
                    /* sanity check to avoid infinite loop */
                    if (left_pos == pos)
                    {
                        decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
                        return false;
                    }
                    left_pos = pos;
                }
                else if (this_frame_sample > target_sample)
                {
                    right_sample = this_frame_sample;
                    /* sanity check to avoid infinite loop */
                    if (right_pos == pos)
                    {
                        decoder->protected_->state = FLAC__STREAM_DECODER_SEEK_ERROR;
                        return false;
                    }
                    right_pos = pos;
                }
            }
        }
    }

    return true;
}
#endif

FLAC__StreamDecoderReadStatus file_read_callback_(const FLAC__StreamDecoder* decoder, FLAC__byte buffer[], size_t* bytes, void* client_data)
{
    client_data;

    if (*bytes > 0)
    {
        *bytes = fread(buffer, sizeof(FLAC__byte), *bytes, decoder->private_->file);
        if (ferror(decoder->private_->file))
            return FLAC__STREAM_DECODER_READ_STATUS_ABORT;
        else if (*bytes == 0)
            return FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM;
        else
            return FLAC__STREAM_DECODER_READ_STATUS_CONTINUE;
    }
    else
        return FLAC__STREAM_DECODER_READ_STATUS_ABORT; /* abort to avoid a deadlock */
}

FLAC__StreamDecoderSeekStatus file_seek_callback_(const FLAC__StreamDecoder* decoder, FLAC__uint64 absolute_byte_offset, void* client_data)
{
    client_data;

    if (decoder->private_->file == stdin)
        return FLAC__STREAM_DECODER_SEEK_STATUS_UNSUPPORTED;
    else if (fseeko(decoder->private_->file, (off_t)absolute_byte_offset, SEEK_SET) < 0)
        return FLAC__STREAM_DECODER_SEEK_STATUS_ERROR;
    else
        return FLAC__STREAM_DECODER_SEEK_STATUS_OK;
}

FLAC__StreamDecoderTellStatus file_tell_callback_(const FLAC__StreamDecoder* decoder, FLAC__uint64* absolute_byte_offset, void* client_data)
{
    off_t pos;
    client_data;

    if (decoder->private_->file == stdin)
        return FLAC__STREAM_DECODER_TELL_STATUS_UNSUPPORTED;
    else if ((pos = ftello(decoder->private_->file)) < 0)
        return FLAC__STREAM_DECODER_TELL_STATUS_ERROR;
    else
    {
        *absolute_byte_offset = (FLAC__uint64)pos;
        return FLAC__STREAM_DECODER_TELL_STATUS_OK;
    }
}

FLAC__StreamDecoderLengthStatus file_length_callback_(const FLAC__StreamDecoder* decoder, FLAC__uint64* stream_length, void* client_data)
{
    struct stat filestats;
    client_data;

    if (decoder->private_->file == stdin)
        return FLAC__STREAM_DECODER_LENGTH_STATUS_UNSUPPORTED;
    else if (fstat(_fileno(decoder->private_->file), &filestats) != 0)
        return FLAC__STREAM_DECODER_LENGTH_STATUS_ERROR;
    else
    {
        *stream_length = (FLAC__uint64)filestats.st_size;
        return FLAC__STREAM_DECODER_LENGTH_STATUS_OK;
    }
}

FLAC__bool file_eof_callback_(const FLAC__StreamDecoder* decoder, void* client_data)
{
    client_data;

    return feof(decoder->private_->file) ? true : false;
}